95 E300 idle speed control code/troubleshooting questions - PeachParts Mercedes-Benz Forum

engatwork · #1 03-09-2009, 09:00 PM

I am in the process of troubleshooting an issue with a 1995 E300 with 240k miles. The initial problem was after starting cold and driving for about 2 miles the throttle would almost seem to "stick". When it did it to me one time it was almost like the engine accelerated. You could take your foot off the gas pedal and it would cruise along at 2000 rpm. One thing I seem to have noticed is that I do not think this issue happens at all once the engine is up to temperature. Keep in mind too that it happens only every now and then. I cleaned and lubed the throttle linkage and it seems to be ok but this was only after driving for one day. I will see if it does it again tomorrow morning on the way to work.

I don't feel that the linkage sticking is the problem but I may be wrong. Anyway, I pulled the trusty home made code reader out on terminal 4 and initially got a code 2 (speed sensor), 3 (ELR temp sensor) and 8 (ELR actuator (Y22), ELR control loop "open circuit". I was able to clear out code 3 and 8 and they have not come back up but code 2 will not clear at all no matter how long I hold the pushbutton down. I checked the resistance through the speed sensor and got 605 ohms which is within spec for the Beru sensor. I even went so far as to swap it with an other speed sensor that was within spec for the brand and I am still getting code 2. I am getting a voltage change from the speed sensor as I rev the engine up and the idle does currently return to spec after revving. The engine wiring harness has been changed and is in good condition.

The manual says the issues that it could be are Plug connection (X26/7), (L3) clearance, dirt), Plug connection, starter ring gear speed sensor (L3x1) and finally wiring.

Now for the questions:
1. Has anyone ever run into this problem before?
2. Why won't the code clear?
3. Where is plug connection X26/7?

Any help or guidance in regards to this issue will be appreciated. Oh yea, I have a 95 E300 just like the one I am trying to resolve issues on sitting right next to it so it is pretty easy to try the different parts as I need to.

Thanks

engatwork · #2 03-10-2009, 06:21 AM

I will probably try the other ELR this afternoon to see if it makes any difference. Anyone have any thoughts on this?

jubjub · #3 03-10-2009, 08:56 AM

Did you clean every linkage? I had the exact same problem in the cold. Worked fine when warm. It was the linkage that goes down between the block and the IP.

iceman805 · #4 10-29-2009, 07:37 PM

Quote:

Originally Posted by jubjub

Did you clean every linkage? I had the exact same problem in the cold. Worked fine when warm. It was the linkage that goes down between the block and the IP.

I have the exact problem, on the exact car at nearly the exact same mileage! Throttle sticks only when the engine is cold at startup and gets worse as the weather gets colder. Usually, I can "tap" the gas pedal and the RPM drops back to "normal" but not when it's cold outside....stays revved up for a WHILE.

Off to try this suggestion before the light fades!

connerm · #5 01-05-2010, 06:12 AM

My 95 is at 240,000 and the idle sticks too when cold. Yesterday it was 30 degrees when I started it. It ran at 2000 rpm for a mile or two. It just started doing this in the last couple of weeks and only when its cold.

engatwork · #6 01-05-2010, 06:17 AM

I have not resolved it yet but do make a point to get on the interstate as soon as I can after starting the car

. I did do a little nosing around and disconnected the linkage where it goes down between the intake and cam cover and it does seem to be sticking between the block and IP. I've got to replace the oil pump and head gasket as soon as I get the shop sorted out and will resolve it while everything is apart.

TimFreeh · #7 01-05-2010, 08:28 AM

Quote:

Originally Posted by engatwork

I did do a little nosing around and disconnected the linkage where it goes down between the intake and cam cover and it does seem to be sticking between the block and IP.

That's likely your problem. Is the OM606 on a MY 95 year a drive-by-wire setup? I guess not?

I don't have a W124/Om606 combo but I've had lots of sticking accelerator problems in cold conditions over the years in MB Diesels and its always been some obscure throttle linkage point that is a pain in the neck to get to.

These kind of linkage points are supposed to be lubed on a semi-regular basis but they never are due to access issues. IIRC Dextron ATF is the specified factory lubricant for throttle linkage pivot points.

alphadeltaromeo · #8 01-06-2010, 06:58 PM

I'm having the exact same issue. I've posted on this before (just never got around to diagnosing and saw this thread today, so posted on it instead of mine), but took things apart when I got home tonight, as this problem is becoming quite annoying and potentially dangerous. I've attached a number of pics that will help me discuss the problem. With that said, I have a number of questions about certain parts that I'm hoping some experienced members can help identify?

You can see in one of the pics that the ball joint on the linkage between the IP and the "unknown to me part" is very sticky/stiff. I popped the one end of the ball joint off and can feel the super stiff nature of the connection on the other side. Every other ball joint connection is very loose, so from a previous post on this thread above, it looks like it's supposed to be lubed and quite free. Is that an accurate assessment?

If so, should I lube with ATF or lithium or ?

engatwork · #9 01-06-2010, 08:20 PM

1st pic is the cruise control, tan thing is a vacuum controller for the transmission. Not sure about the microswitch.

alphadeltaromeo · #10 01-06-2010, 08:55 PM

Jim - thanks much for the reply on the identification!

Update on the idle issue...the sticky ball joint connections on the cruise-to-IP connection were taken apart. I cleaned the ball joint ends with brake cleaner and lubed the connections with white lithium grease. This has completely solved the issue.

I'm feeling rather blessed that it wasn't something else.

alphadeltaromeo · #11 01-06-2010, 08:59 PM

Thoughts on what this connection is?

engatwork · #12 01-06-2010, 09:22 PM

That is a switchover valve for the vacuum actuator that controls the "dampers" located in the intake manifold.
Thanks for the comments on this post. Maybe it will help me move this "project" to a higher priority on the "to do" list. It has been a couple weeks since I drove the car.

engatwork · #13 01-10-2010, 08:09 AM

I went through this exercise yesterday afternoon (took about 1-1/2 hours) on the wife's E300 and in 25 dF weather this morning it performed flawlessly with no sticking at all. I may do the one on my car later today.

Deezl · #14 01-13-2010, 11:52 PM

Alpha, thanks for posting this - very helpful.

Ka-T · #15 02-08-2017, 03:40 PM

Do you have to remove the intake manifold to get to the throttle linkage?