M104 throttle linkage question - PeachParts Mercedes-Benz Forum

amg280 · #1 02-02-2009, 02:15 PM

A few days ago, my 95 E320's throttle started acting very peculiar. If you even breathed on the gas pedal, it would take off and spin the tires. after lubing up the linkages, the problem persisted. I looked in there today, and noticed there is one return spring. Should there be another spring? Does anyone have a pic or a diagram? This is really annoying. I would say at about 1/5 throttle, it feels like its floored. The car has ASR, if that makes a difference. It idles and drives fine otherwise, no check engine light. The throttle is just not progressive at all anymore. The cable is adjusted properly. Please help.

deanyel · #2 02-02-2009, 03:07 PM

Should be this one - http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=124032&M=104%2E992&GA=722%2E369503&GM=717%2E450&CT=M&cat=520&SID=07&SGR=160&SGN=09 Check the fault codes too, especially pin 14.

Kestas · #3 02-03-2009, 09:37 AM

I agree with checking for codes, even if the check engine light is not on.

Another thought - maybe you have a bad ETA (electronic throttle actuator). This car is throttle-by-wire and your symptom may be related to a bad ETA. They are made with the same disintegrating insulation as the engine wiring harness, and in my opinion should be rebuilt as a preemptive measure, just like the engine wiring harness.

Are you sure your engine wiring harness has been replaced? In an earlier post you mention that it looks good. Can you double check?

amg280 · #4 02-03-2009, 10:16 AM

Hi. Yes I have receipts from the PO to prove it. Both the engine harness and EA harness have been replaced in the last 15K miles. The EA itself hasnt been replaced, I hope that is not bad though. I think it may be something as simple as a spring. In the above mentioned diagram, It shows 2 springs. I can only find one. Its a pain to diagnose since the intake it directly over it. The next warm day I will see if I can get a better look. I noticed that when pulling on the linkage (attached to the throttle cable), the secondary linkage (going to EA) is kind of lazy. The secondary linkage wont retract on its own, the first linkage pushes the secondary linkage back to the closed position. The diagram shows a spring on the second linkage so hopefully that is my problem. A cheap fix is always a welcome addition.

amg280 · #5 02-07-2009, 09:27 PM

Well I found the problem. There are two springs in the whole linkage assembly. The spring that you cant see in plain sight was broken due to corrosion. This spring attaches under the intake near the electronic throttle. I had to take the oil filter cap off to shimmy my hand in there to replace it.

Thanks for the diagram!