OT: The mechanic is stumped, how about you?

[William]

So I figured I would try running this past the forum collective since the breadth of knowledge demonstrated here is quite diverse and deep….and my usual shop seems to be stumped at the moment.

So one of my cars has been having intermittent stalling issue for a little while now. It’s an 07 Honda Element SC with a five speed manual transmission. This is how the issue usually presents itself…

Starting up from cold is not an issue. I usually let it warm up for a while before I take off. Within a couple of miles if I come to a stop sign or light and take the car out of gear it will stall. Knowing this as I come up to a place I know I will have to stop I will take it out of gear and let the revs fall to see if it will try to stall. If it stalls I will put it back into gear to compression start it and then try it again. Usually it will stall at least twice, sometimes three times before it will finally stop and stay running. Once this happens it will run fine until I stop somewhere for more than a couple hours, and then it will do it all over again. If it’s just a short stop somewhere it starts and runs fine.

So far the mechanic can’t find anything wrong with it and is scratching his head. No codes being thrown or any other indications.

Just curious if there are any thoughts or other Element owners that have encountered the same issue?






W.

[Ralph]

Water in fuel. Fuel filter clogged. (maybe the Element doesn't have a filter, but a sock like thing)

[unterhausen]

could be running lean. Bad o2 sensor?

I was going to say MAF, but I think that would trigger the O2 sensor

[jemoryl]

I had a car with a bad O2 sensor that exhibited similar behavior, but was not throwing a CEL code. My mechanic figured it out.

[josephr]

my first thought was the spring was worn out on the automatic choke on carburetor, but that's kind of hard to do with EFI. :rolleyes: Maybe a new airflow sensor in the throttle body? Leaky vacuum hose or condensation in a vacuum hose that's freeezing/thawing/refreezing?

[unterhausen]

my honda had a leaking manifold gasket under the carb. So it ran lean. Same exact driveability problems. Got great gas mileage though.

I wonder if a leaky gasket on the inlet side would cause this problem without triggering a code

[donevwil]

How smoothly does it idle after warm up? Any roughness, stumbling? I experienced something similar with a high mileage minivan, it had both an inconsistent, poor idle with occasional stalling. It was due to plugged or very dirty injectors tracked down (by shear accident) to poor gas quality. It improved when I filled up at a new station, but ultimately had to have the injectors professionally cleaned (beyond what an additive could accomplish).

[Spoker]

Extra lean mixture in the fuel map when out of gear?

[Louis]

my first thought was the spring was worn out on the automatic choke on carburetor, but that's kind of hard to do with EFI. :rolleyes:

I was going to say carburetor icing, if it happened only on wet and damp days....

(Used to happen on the 318 engine in my '73 Charger, due to excessive carbon build-up in the intake crossover passage that was intended to provide heat to the base of the carb. I removed the intake, had it "boiled out" and the problem never came back.)

[AngryScientist]

Idle Air Control Valve.

Makes sense, since it runs OK at idle when you first start it, but has an issue once warmed up.

if it was water in the fuel or clogged fuel filter, that would show up at other areas in the power band, particularly at high fuel demand, with some sputtering and power cuts.

could be a whole bunch of other things too, including worn valves that arent sealing right, a bad EGR valve or other vacuum leak. could easily be a bad o2 sensor or MAF sensor, but those generally do throw codes.

good luck!

[GScot]

IAC as mentioned is a candidate. Trying to think about sensors that could work cold and fully up to temp but not deliver proper signal during warmup. Intake Air Control is a valve rather than a sensor but the simplest thing to try I think. If Honda would let you plug into the OBD and log everything you could figure it out but I don't think that is an option short of having dealer equipment.

[parris]

I ran into a similar issue with my Subaru this past year. It turned out that the egr valve was slowly failing. When it finally croaked I couldn't get the car to idle and it would die at every stop. My car's also a standard like you Honda. I took it to 2 different mechanics that checked codes. One said they couldn't find anything wrong and the second said I needed a new engine. I took it to a third good mechanic and he was the one that properly diagnosed and fixed the problem. HE was willing to go beyond what the computer was telling him and test drove the car as well as blocking off the egr with a plate to make sure of his diagnosis.

Oh and the problem didn't show until the engine was up to temp.

Hope this helps.

[David Kirk]

Idle Air Control Valve.

Makes sense, since it runs OK at idle when you first start it, but has an issue once warmed up.

if it was water in the fuel or clogged fuel filter, that would show up at other areas in the power band, particularly at high fuel demand, with some sputtering and power cuts.

could be a whole bunch of other things too, including worn valves that arent sealing right, a bad EGR valve or other vacuum leak. could easily be a bad o2 sensor or MAF sensor, but those generally do throw codes.

good luck!

I agree - AIC control gummed up and sticking.

dave

[fmradio516]

I also have had experienced this with an idle control valve. my usual shop had my car for weeks and couldnt figure it out. I finally took the car back and brought it to the stealer and they fixed it with a new valve for a couple hundred bucks.

[froze]

This issue you have is shared with the Fit as well.

The next thing to do is to clean the Idle Air Control Valve, this is easy, in fact I was able to find a video on YouTube you can watch and do it yourself: https://www.youtube.com/watch?v=7MQ2EkmYtyA If after watch this video and you're laughing at me for saying it's easy to do then ask your mechanic to do it, of course that will cost money and there is no guarantee that I'm right and that's the problem.

The other issue which I'm leaning more towards then the rest of the stuff I'll mentioned is the valves are out of adjustment, but when this problem only occurs when cold then the valve clearance is a problem, and Honda engines are very picky about their valve adjustment and it has to be very precise to factory specs.

Another problem the Element had was a poor ignition switch which wore out rather quickly. In the early stages of this failure that once the ignition switch warms up it keeps contact, but when cold it may not, it's easy test, simply start the car then wiggle the key while it's in the ignition and see of the engine cuts off. I don't think this is your problem but let's eliminate that from the list fast by testing it.

I assume the mechanic ran all the computer diagnoses stuff on the car, if that's true then the mechanic needs to go where computers don't go, and run a compression test. From what I've read the engine in your car is not up to typical Honda standards and they had problems with compression failure in the #2 cylinder mostly from what I've read, if yours proves to be the same case (regardless of which cylinder) I'm surprise a recall hasn't been generated. Also the mechanic should run a vacuum check on the engine, a vacuum check is one of the most important diagnoses that can be done on an engine, it can show all sorts of stuff that could be wrong.

Ok, so if this was my car and I didn't know a whole lot about mechanical stuff I would first test the ignition switch myself, it's easy to do and it eliminates (or prove) that being the problem fast and cheap. If the ignition passes the wiggle test then I would take the car to the shop and tell them you want a compression and a vacuum test done to rule out anything going on in those areas. Next you want the idle air control valve checked and cleaned, and you want your valves adjusted. Is this stuff going to cost you money? Sorry to say, but yes it will; will it fix the problem, I'm not there to see and test the car so working remotely is tough to do plus I'm a backyard mechanic not one by trade, so all I can say is that I hope it will, but I can't guarantee you that it will, but I am about 75% sure it will. It's important that the mechanic first does the vacuum test, then if necessary due to a problem in the readings from the vacuum test do the compression test, at the very least those two tests will give you the peace of mind that the engine is good.

Just so you know what a vacuum test can find read this: http://www.gregsengine.com/using-a-vacuum-gauge.html Some of the stuff that is looked for in this test can cause a problem similar to what you described, like valves and even compression leaks can be detected. Once a compression leak has been detected using a vacuum gauge then the mechanic can run a compression test on each cylinder to find out which one is having the problem. Problem is once that has been found it's rather expensive to fix...think new engine. But don't get to worried about affording a new engine yet, do the Idle Air Control Valve and the valve adjustment and I think you will be good to go.

[BobbyJones]

The above post is pretty concise... I’ve got nothing to add but a question or two:

What happens if you clutch in and “feather down” rpms to idle?

Or if you hold a steady 2k in neutral for a minute and let off the accelerator?

Just curious.

[mtechnica]

Does it stall only when it's idling in neutral with no gas pedal input or is it possible to keep it from stalling by pressing on the gas while it idles?

[William]

Thanks for the insightful replies folks! A number of things to look into and hopefully we aren't talking "new engine". :)

When this happens I can keep it running if I work the gas pedal but if I take it off it will stall. After start up (and I can let it warm up for quite a while) I can press the gas pedal and run it up to 2000 plus rpms and let off the gas and it will go back to idle. I can also do this after the stalling phase has happened. Sometimes though I have noticed that as the rpms fall it sometimes drops further almost like it's going to stall but then the idle jumps back up to keep it running.

I wouldn't say it's been idling rougher, but I did notice a slight loping to it.








W.

[Ken Robb]

I also have had experienced this with an idle control valve. my usual shop had my car for weeks and couldnt figure it out. I finally took the car back and brought it to the stealer and they fixed it with a new valve for a couple hundred bucks.

So, if the dealer quickly solved a problem that your independent tech couldn't figure out over two weeks and the cost was a couple of hundred parts and labor is it fair to call him "stealer"?

[fmradio516]

So, if the dealer quickly solved a problem that your independent tech couldn't figure out over two weeks and the cost was a couple of hundred parts and labor is it fair to call him "stealer"?



Not in this situation! But usually yes.


Sent from my iPhone using Tapatalk

[likebikes]

my 08 honda had a very similar issue.

i replaced coil packs/spark plugs and it ran better, but the stalling still happened.

i then did a valve adjustment and the problem stopped.

[unterhausen]

So, if the dealer quickly solved a problem that your independent tech couldn't figure out over two weeks and the cost was a couple of hundred parts and labor is it fair to call him "stealer"?

I was going to ask the OP if he had taken it to a dealer. Stuff like this is when it seems like a good idea to take it to the dealer. Generally, google reveals the answer and I fix it myself, but someone that doesn't do that is often well served to pay the premium that a dealer charges.

[ultraman6970]

Since is stalling or turning off well could be the TPS. Throttle position sensor. When that thing fails or start reading wrong the engine just starts going off or starting and shutting off... the other problem since the car is manual could be the clutch.

[Steve in SLO]

Probably just a bad turbo-encabulator

https://youtu.be/Ac7G7xOG2Ag

[R3awak3n]

I would take it to a different mech.

I had a car a few years ago, took it to a mechanic that soent weeks with it, could not figure it out. Told me old cars are like old people, have to drive them carefully or they break. Car was feom 2004 and that is a bs excuse for a problem this guy had no idea how to solve. Because I had an inspection, I needed this solved or car would not pass.

Took it to this other mech. He told me, there are 2 kinda of mechs out there. Cheap and crap and expensive and good.... of course he was the latter. I looked at him and rolled my eyes but wanted him to put his money where his mouth is.
Well.... got a call at end of the day, car is ready. I was sure was gonna get the engine light in 20 miles because thats what had happened like 5 times with the old guy.

Nope. Dude said it was a short and he took half the car appart to find it. Also fixed some other **** the other mech did not put back correctly. Was not cheap but I was very ok spending the money on someone who knew what he was doing.

I do think there is a 3rd kindnof mech the expensive and crap (I took the car to the dealership too and they too made up a bunch of excuses to what could be and had no idea)

But even if your mech ia great, it would not be atupid to get another pair of eyes in it.

[d_douglas]

I love these cars. I kinda look for them for sale locally, but they’re always 250000km or more. I guess there is a reason that so many people use them for so long.

[sitzmark]

A quick search suggests the OP's issue is shared by many others. A number of different variations with rough and low idle when cold to engine stopping. Reported to be fine after 5-10 minutes of driving and engine coolant temp warms up. Reports of TPS and coolant sensor codes when sensors involved.

One report of electrical system failure just prior to engine stopping, then electrical returns (radio for example) but engine must be restarted. Once driven for a while the problem goes away.

Another reported fix was intake valve re-torque - all "loose". Plausible explanation as valve/securing materials would expand as temp rises and theoretically "tighten" the connection. Intake "Valve job" (re-troque and new cover gasket -$75) solved the problem for good.

For good or bad ... does not appear to be a unique problem. Unfortunately lots of stuff to chase down. Good luck and hope you find fix soon.

[cmg]

On the 98 Civic that did this we replaced the spark plug wires and distributor. The valve cover leaked oil into the spark tubes and the constant burning oil cracked the ends and the plug would side discharged when under load. That and the Idle Air Control Valve is a good start.

[josephr]

I was going to say carburetor icing, if it happened only on wet and damp days....

(Used to happen on the 318 engine in my '73 Charger, due to excessive carbon build-up in the intake crossover passage that was intended to provide heat to the base of the carb. I removed the intake, had it "boiled out" and the problem never came back.)

and during the hot summers did you get vaporlock?...based of the other comments, I'd surmise the air intake idle vacuum-controled fuel control modulating valve is distorting the electronic sensor information input/feedback mechanism of the throttle body flow meter yielding decreased fuel pressure input.

[William]

You folks are good! I had a list of possibilities I was going to ask them about this morning...

I got a call from the shop before I was able to call them. They ran down a list of checks including checking the TPS and the idle air control. They then did the compression and vac check and got a squiffy (my term) reading and removed the valve covers to find the valves needed adjustment. I was at the gym at the time but they said either the exhaust valves were loose and the intake was too tight or vice versa. I'm going to stop by the shop in a little while to get the read.




You folks are awesome!:cool:







W.

[Blown Reek]

What color is your Element?

[William]

What color is your Element?

Nighthawk Black Pearl.







W.

[likebikes]

called the valve adjustment.

[froze]

You folks are good! I had a list of possibilities I was going to ask them about this morning...

I got a call from the shop before I was able to call them. They ran down a list of checks including checking the TPS and the idle air control. They then did the compression and vac check and got a squiffy (my term) reading and removed the valve covers to find the valves needed adjustment. I was at the gym at the time but they said either the exhaust valves were loose and the intake was too tight or vice versa. I'm going to stop by the shop in a little while to get the read.




You folks are awesome!:cool:



W.

That's what I thought, the valves sounded logical and the compression and vac test verified that. Congrats the car is like new again.

One thing to keep in mind with Acura's, their engines tend to have very close tolerances so they don't tolerate fail to service the car properly type of abuse. You need to make sure the oil gets changed, if your car is like mine it will give you a percentage of oil left, I change mine when it gets down to 20%, I don't wait till it's at 0%. Dirty oil will make so you have to adjust your valves more often, and use a good grade of full synthetic oil; not sure about all Acura dealers but mine uses oil with the Acura name on it which according them is Castro, but Castro, Valvoline and Mobil are all very good oils. When your engine gets a lot miles on like 100,000 miles plus you could switch from 0-20 weight to 5-20 in normal N American weather or 5-30 if you live in a hot climate like Southern California etc.

Also do not use anything less than premium fuel, however occasionally you can mix half a tank of premium and half a tank of middle grade you'll be fine, but running mid or regular can damage the engine over the long haul, also make sure you're not using a gas with more than 10% alcohol as this will cause all sorts of problems; I use mostly Shell premium, sometimes if traveling I might use Exxon/Mobil or Chevron; I have read that Costco gas is very good but when I used it I didn't like how the Acura was running so I haven't gone back to them; but with the 3 that I mentioned you can find those anywhere, where I live Exxon/Mobil and Chevron are not in my city which is why I use mostly Shell. Anyway trying to go cheap on the cost of fuel for an Acura is not a good idea.

[William]

I'm pretty much 100% on using Shell, occasionally I'll use another brand but that only happens when I'm traveling. I'm also pretty religious on changing the oil at regular intervals and not letting it go down to 0% .

Amazing how you don't really notice the gradual decrease in power until you get the problem fixed and then you notice the difference was huge.






W.

[Mikej]

Hondas are infamous for exhaust valves getting tight, especially the one the 3.5 v6 in the back that you cant reach.

[alancw3]

so do those honda engines have solid lifters instead of hydraulic? most american made cars have hydraulic lifters that never need to be adjusted. i have had both and i can say why have solid lifters in todays world? hydraulic are just bullet proof even in high performance engines.

[GScot]

so do those honda engines have solid lifters instead of hydraulic? most american made cars have hydraulic lifters that never need to be adjusted. i have had both and i can say why have solid lifters in todays world? hydraulic are just bullet proof even in high performance engines.

Overhead cam design where solid lifters are a better option. Typically they are easy to adjust and require few adjustments compared to solid lifters of simpler overhead valve engines. Subaru also uses solid lifters but pretends they never need service.

[Lewis Moon]

So I figured I would try running this past the forum collective since the breadth of knowledge demonstrated here is quite diverse and deep….and my usual shop seems to be stumped at the moment.

So one of my cars has been having intermittent stalling issue for a little while now. It’s an 07 Honda Element SC with a five speed manual transmission. This is how the issue usually presents itself…

Starting up from cold is not an issue. I usually let it warm up for a while before I take off. Within a couple of miles if I come to a stop sign or light and take the car out of gear it will stall. Knowing this as I come up to a place I know I will have to stop I will take it out of gear and let the revs fall to see if it will try to stall. If it stalls I will put it back into gear to compression start it and then try it again. Usually it will stall at least twice, sometimes three times before it will finally stop and stay running. Once this happens it will run fine until I stop somewhere for more than a couple hours, and then it will do it all over again. If it’s just a short stop somewhere it starts and runs fine.

So far the mechanic can’t find anything wrong with it and is scratching his head. No codes being thrown or any other indications.

Just curious if there are any thoughts or other Element owners that have encountered the same issue?






W.

If this were a BMW E30 I'd say idle control valve.

[redir]

I wish I could help ya but I can't. I've been trouble shooting the same damn problem over the last 6 months on my '94 E420 Mercedes. Driving me crazy and about to just give up on the whole car.

[Ralph]

I had a 2010 Honda Element. (post is about a 2007) hydraulic valves, and a timing CHAIN. And it ran on 87. No need to use premium....and no advantage to premium. Actually.....premium fuel just has more anti knock additives ....so is less volatile (to not pre ignite with higher compression)......and in theory.....has less energy content...although maybe not measurable. (couldn't measure burn rate difference on dyno)

If I were to enter a gas mileage contest at or near sea level....would want to use 87 (or even mountain 85 if it didn't pre ignite....or knock) I know....just opposite of what most think.

[Mikej]

so do those honda engines have solid lifters instead of hydraulic? most american made cars have hydraulic lifters that never need to be adjusted. i have had both and i can say why have solid lifters in todays world? hydraulic are just bullet proof even in high performance engines.

Because V-TEC

[William]

In the years that I've had this vehicle this is the first issue (other than brakes and other wear items) I've had so I think its been a pretty solid car so far.






W.

[froze]

I wish I could help ya but I can't. I've been trouble shooting the same damn problem over the last 6 months on my '94 E420 Mercedes. Driving me crazy and about to just give up on the whole car.

6 months and no one knows what is going on? So what are the symptoms you're experiencing?

I don't know anything about MBZ's but I can't believe it would be that difficult to resolve...but maybe! Most of this stuff is simple diagnoses, if using a MBZ diagnoses computer, yes, you do have to use brand specific diagnoses software NOT a generic one because for some reason the generic ones leave out some codes, doesn't find the problem then you have to resort to mechanical diagnoses like compression and vacuum gauge tests like what helped the OP with his issue to make sure it was the valves as I suspected. And a lot of times these issues are pretty much common with whatever the symptoms are narrowing it down to just 2 or 3 different things. That's all I did to figure out William's issue, and had it narrowed down to the valves as the primary cause which the compression and vacuum tests confirmed my suspicions. What I can't believe is that some backyard mechanic with no formal training like myself figured this out for William but mechanics were stumped?! And I'm not that good of a backyard mechanic!! Geez, anyways give us your symptoms and lets see if I, or someone here who understands MBZ, gets lucky twice in a row.

I use to work on my classic cars (I sold off all but one over the last year and half) and my deceased friends classic cars and was always pretty good with diagnosing stuff; while today's cars have electronics systems the basic underlying mechanical diagnoses (when the computer diagnoses fails to find a problem, or sometimes they say it's one thing but it's not leading to useless and expensive parts replacements) is the same regardless if it's a vintage or modern car. There are some things that go wrong with modern cars I don't bother to fix, mostly because I don't want to spend a day or two disassembling most of the car to get to something, plus modern cars require a lot more tools then I can afford to buy, so even I go off to a mechanic, but that's AFTER I've diagnosed the issue myself, then I casually tell the mechanic this: "do you think it might be this?", I never tell a mechanic that I know it's something because they don't like to be told their job, so I play stupid with them, and at least 9 times out of 10 I'm right, and by me knowing something it prevents getting ripped off. And a lot of mechanics today aren't being taught how to do mechanical diagnoses, they're taught to go off what the computer says, which leads to what I said earlier, most mechanics today are parts replacers.

[Gummee]

I wish I could help ya but I can't. I've been trouble shooting the same damn problem over the last 6 months on my '94 E420 Mercedes. Driving me crazy and about to just give up on the whole car.

My Dad's 95 S-Class needed a new engine wiring harness. The greens influenced Mercedes to put bio-degradable covering on the wires in the engine bay. So guess what bio-degraded over the years?

It wasn't too bad a job to DIY, just expensive (like everything else Mercedes)

M

[cmg]

In the past when i have a Honda problem that is difficult i do a search among the many Honda forums. a simple google search will lead you to the nearest site. this one was fun, on to next.....

[GScot]

In the past when i have a Honda problem that is difficult i do a search among the many Honda forums. a simple google search will lead you to the nearest site. this one was fun, on to next.....

No kidding. Honda has a very helpful community. My wife had a series of Preludes until they stopped making them. The last one was a great car for 17 years. Maintenance and one column switch issue which turned out to be a mess. I fix everything myself and that involved the immobilizer which made it a supposedly dealer only item. With help from the Honda community and some improv I managed to get it working. Dealer wanted $600 plus towing to reprogram the car for the new switch and keys. It took some desoldering and luck but I managed to put the original sensor in the new switch assembly and changed the tumblers to match the old key.

I'm now into VW/Audi and really appreciate the open system. With a cable from Ross Tech you can get into the car's computer and see or even change just about anything. As I understand it BMW allows similar owner access but I have no experience with it. I'm unaware of any other auto manufacturers that make it so easy for the diy mechanic. Would love to hear about it if someone has some experience.

[csm]

I had a 2010 Honda Element. (post is about a 2007) hydraulic valves, and a timing CHAIN. And it ran on 87. No need to use premium....and no advantage to premium. Actually.....premium fuel just has more anti knock additives ....so is less volatile (to not pre ignite with higher compression)......and in theory.....has less energy content...although maybe not measurable. (couldn't measure burn rate difference on dyno)

If I were to enter a gas mileage contest at or near sea level....would want to use 87 (or even mountain 85 if it didn't pre ignite....or knock) I know....just opposite of what most think.



I have a 2010 as well. Most recent tank was over 24 mpg in a mix of highway and city. It's my second one. I've tried higher octane and tracked the mileage. Basically no difference from 87. Just turned 100k miles. Hope it goes another 100k b/c there's nothing out there to replace it yet.


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[Chris]

Could be the distributor, could be the coil - TW

[ultraman6970]

A bad coil will turn off the car? coils go bad in sections, personally never seen a coil turning off an engine completely. THe coil if bad will turn off just one or the cylinders that went bad in the coil, but who knows to be honest.

Had a bad coil and sucks to drive home in 5 or 3 cylinders, easy to test tho... just unplug the cables one by one and see if the car starts stuttering, if the cable disconnected doesnt do nothing to the engine (it should) then you sure have a coil problem.

[Ken Robb]

Older cars have a single coil unlike newer cars that often have separate coils on each spark plug. When the single coil fails your engine stops. They can fail sporadically often due to thermal expansion/contraction causing shorts or open circuits.

[Chris]

A bad coil will turn off the car? coils go bad in sections, personally never seen a coil turning off an engine completely. THe coil if bad will turn off just one or the cylinders that went bad in the coil, but who knows to be honest.

Had a bad coil and sucks to drive home in 5 or 3 cylinders, easy to test tho... just unplug the cables one by one and see if the car starts stuttering, if the cable disconnected doesnt do nothing to the engine (it should) then you sure have a coil problem.

It’s a Tom Waits (TW) lyric. I know nothing about cars. It was a joke. :)

[redir]

6 months and no one knows what is going on? So what are the symptoms you're experiencing?

I don't know anything about MBZ's but I can't believe it would be that difficult to resolve...but maybe! Most of this stuff is simple diagnoses, if using a MBZ diagnoses computer, yes, you do have to use brand specific diagnoses software NOT a generic one because for some reason the generic ones leave out some codes, doesn't find the problem then you have to resort to mechanical diagnoses like compression and vacuum gauge tests like what helped the OP with his issue to make sure it was the valves as I suspected. And a lot of times these issues are pretty much common with whatever the symptoms are narrowing it down to just 2 or 3 different things. That's all I did to figure out William's issue, and had it narrowed down to the valves as the primary cause which the compression and vacuum tests confirmed my suspicions. What I can't believe is that some backyard mechanic with no formal training like myself figured this out for William but mechanics were stumped?! And I'm not that good of a backyard mechanic!! Geez, anyways give us your symptoms and lets see if I, or someone here who understands MBZ, gets lucky twice in a row.

I use to work on my classic cars (I sold off all but one over the last year and half) and my deceased friends classic cars and was always pretty good with diagnosing stuff; while today's cars have electronics systems the basic underlying mechanical diagnoses (when the computer diagnoses fails to find a problem, or sometimes they say it's one thing but it's not leading to useless and expensive parts replacements) is the same regardless if it's a vintage or modern car. There are some things that go wrong with modern cars I don't bother to fix, mostly because I don't want to spend a day or two disassembling most of the car to get to something, plus modern cars require a lot more tools then I can afford to buy, so even I go off to a mechanic, but that's AFTER I've diagnosed the issue myself, then I casually tell the mechanic this: "do you think it might be this?", I never tell a mechanic that I know it's something because they don't like to be told their job, so I play stupid with them, and at least 9 times out of 10 I'm right, and by me knowing something it prevents getting ripped off. And a lot of mechanics today aren't being taught how to do mechanical diagnoses, they're taught to go off what the computer says, which leads to what I said earlier, most mechanics today are parts replacers.

Well 6 month's and I don't know what's going on. I've not taken it to a mech but there really arn't any around here worth a darn, at least for older Mercedes anyway.

I had noticed this behavior with the car for a while, while driving it would seem to misfire a bit but then it would 'kick in' and run great. Episodes occurred rarely. At some point I started leaking coolant and figured out it was the water pump. SO I replaced that, not an easy job on an M119 engine. While I was at it I replaced the cap and roters on both distributes, fixed the leaking power steering fluid reservoir, replaced a whole bunch of hoses and the main serpentine belt. I also replaced the fuel filter and the fuel pump.

I then got the car inspected and was good to go for another year when it started acting up. I would first notice the misfiring and then the car had barely enough power to make it up the small hill to my house. It would 'kick in' and then be fine. But it got progressively worse. From stops when I accelerated it would stall. The loss of power was accompanied by rotten egg smell.

So since then After finding thie thread which was almost my case to a tee: https://www.500eboard.com/forums/showthread.php?t=12240 I replaced the two coils to no avail.

Here's what it sounds like: https://photos.app.goo.gl/pUgtaxdEnBwFHNJS6

So out of the work that I recently did there are a few things that could cause the issue. But I have truple checked everything, plugs, distributers and fuel. I checked the fuel pressure on the rail and it's perfect so I know it's getting fuel. https://photos.app.goo.gl/Gm7YYNTw4FWM5qu99

I checked for vacuum leaks too and could not find any but I used the propane torch method and I'm not convinced it worked very well so that might be worth investigating more.



My Dad's 95 S-Class needed a new engine wiring harness. The greens influenced Mercedes to put bio-degradable covering on the wires in the engine bay. So guess what bio-degraded over the years?

It wasn't too bad a job to DIY, just expensive (like everything else Mercedes)

M

Yup that was a problem with all those era cars. I don't think there are many even running today that have not had the harness replaced. Mine was replaced many years ago.

[Ken Robb]

Well 6 month's and I don't know what's going on. I've not taken it to a mech but there really arn't any around here worth a darn, at least for older Mercedes anyway.

I had noticed this behavior with the car for a while, while driving it would seem to misfire a bit but then it would 'kick in' and run great. Episodes occurred rarely. At some point I started leaking coolant and figured out it was the water pump. SO I replaced that, not an easy job on an M119 engine. While I was at it I replaced the cap and roters on both distributes, fixed the leaking power steering fluid reservoir, replaced a whole bunch of hoses and the main serpentine belt. I also replaced the fuel filter and the fuel pump.

I then got the car inspected and was good to go for another year when it started acting up. I would first notice the misfiring and then the car had barely enough power to make it up the small hill to my house. It would 'kick in' and then be fine. But it got progressively worse. From stops when I accelerated it would stall. The loss of power was accompanied by rotten egg smell.

So since then After finding thie thread which was almost my case to a tee: https://www.500eboard.com/forums/showthread.php?t=12240 I replaced the two coils to no avail.

Here's what it sounds like: https://photos.app.goo.gl/pUgtaxdEnBwFHNJS6

So out of the work that I recently did there are a few things that could cause the issue. But I have truple checked everything, plugs, distributers and fuel. I checked the fuel pressure on the rail and it's perfect so I know it's getting fuel. https://photos.app.goo.gl/Gm7YYNTw4FWM5qu99

I checked for vacuum leaks too and could not find any but I used the propane torch method and I'm not convinced it worked very well so that might be worth investigating more.





Yup that was a problem with all those era cars. I don't think there are many even running today that have not had the harness replaced. Mine was replaced many years ago.
Even though your fuel pressure is good when you check it at idle it might be insufficient at higher speeds due to partly blocked fuel filter and/or weak fuel pump(s). I had a similar problem with my 1985 BMW 535i years ago. The supply pump in the tank had quit but the high pressure pump could suck enough fuel from the tank for the car to run when I wasn't asking for full power.

[froze]

Well 6 month's and I don't know what's going on. I've not taken it to a mech but there really arn't any around here worth a darn, at least for older Mercedes anyway.

I had noticed this behavior with the car for a while, while driving it would seem to misfire a bit but then it would 'kick in' and run great. Episodes occurred rarely. At some point I started leaking coolant and figured out it was the water pump. SO I replaced that, not an easy job on an M119 engine. While I was at it I replaced the cap and roters on both distributes, fixed the leaking power steering fluid reservoir, replaced a whole bunch of hoses and the main serpentine belt. I also replaced the fuel filter and the fuel pump.

I then got the car inspected and was good to go for another year when it started acting up. I would first notice the misfiring and then the car had barely enough power to make it up the small hill to my house. It would 'kick in' and then be fine. But it got progressively worse. From stops when I accelerated it would stall. The loss of power was accompanied by rotten egg smell.

So since then After finding thie thread which was almost my case to a tee: https://www.500eboard.com/forums/showthread.php?t=12240 I replaced the two coils to no avail.

Here's what it sounds like: https://photos.app.goo.gl/pUgtaxdEnBwFHNJS6

So out of the work that I recently did there are a few things that could cause the issue. But I have truple checked everything, plugs, distributers and fuel. I checked the fuel pressure on the rail and it's perfect so I know it's getting fuel. https://photos.app.goo.gl/Gm7YYNTw4FWM5qu99

I checked for vacuum leaks too and could not find any but I used the propane torch method and I'm not convinced it worked very well so that might be worth investigating more.





Yup that was a problem with all those era cars. I don't think there are many even running today that have not had the harness replaced. Mine was replaced many years ago.


Rotten egg smell? have you had the catalytic converter checked? Take the car down to an exhaust specialist and get it checked; but if you have some mechanical skills you can check it yourself, simply watch this video, (a lot easier than me typing a bunch of crap) and then get back to us as to how it went. This is my primary diagnoses for your car due to the odor you said you have. https://www.google.com/search?q=how+to+check+if+the+catalytic+converter+i s+bad&oq=how+to+check+if+the+catalytic+converter+is+bad&aqs=chrome..69i57j0l5.10131j0j4&sourceid=chrome&ie=UTF-8#kpvalbx=1 Those cats will indeed get progressively worse as the cat fails and thus your performance. If the cat is bad try to get a free flowing cat, they are a honeycomb construction instead of pebbles which is more restrictive, they usually are sold as performance cats, they are not any louder than a normal cat so don't worry about the sound, but your performance and gas mileage will be about 2 to 4 mpg more than it was before the cat plugged up.