'94 E320t Problems - Where Do I Start? - PeachParts Mercedes-Benz Forum

RobertFini · #1 05-02-2010, 12:17 AM

I am having some serious drivability problems with my "new" 1994 E320 tourenwagen and don't know where to start to get these things corrected. I violated my own prime directive when I bought this car: "There is nothing so expensive as a cheap Mercedes."

But it was so beautiful and in really good visual condition and it only had 137k miles on it, plus it has heated seats and I am a total sucker for heated seats. The previous owner had a receipt for a head gasket replacement at 124k, but very few other records. I bought this car to support my new business that takes me to racetracks and motorsports parks, and I've put 10k miles on it since I bought it about two months ago.

It starts right up when it's cold, but sometimes (not always) takes a lot of cranking to start when it's hot. The car has a really bad hesitation whenever I put my foot into the accelerator no matter whether the engine is hot or cold, chugging and sputtering and surging and sometimes backfiring. But when the revs build and I begin to back out of the throttle, it starts to pull like a freight train and runs like a scalded dog, definitely letting me feel the kinship with my C36AMG.

I am not getting a "Check Engine" light but I built one of those tester thingamajigs and downloaded the CS1000 Fault Code Scanner manual, and today I pulled codes from it as listed below, with my interpretations from the CS1000 manual listed in parentheses:

DM Code 5 (Exhaust gas recirculation faulty)
DM Code 6 (Idle speed control faulty)
DM Code 8 (Engine coolant temperature sensor open circuit)
DM Code 10 (Voltage at mass air sensor too high/low)
DM Code 16 (Closed throttle position information faulty)
DM Code 24 (Starter ring gear segments and/or crankshaft position sensor faulty)
Socket 6 (SRS/Airbag) Code 2 (SRS Control unit self test failure)
Socket 6 (SRS/Airbag) Code 8 (Voltage supply interrupted)
Socket 8 (HFM-SFI) Code 13 (O2S/Lambda control system operating at rich or lean limit)
Socket 14 (CC-ISC) Code 5 (Stop lamp switch)
Socket 14 (CC-ISC) Code 6 (Starter lock-out/backup lamp switch)
Socket 14 (CC-ISC) Code 14 (Closed throttle position contact switch)

With all these codes showing, I am mortified at the possibility that the engine wiring harness needs replacing, but a visual inspection reveals no cracking or flaking and I cannot find any cracked or broken vacuum lines in the engine compartment.

I would love to hear some suggestions on where to begin with diagnosing this can of worms.