New behavior at start-up..W124
 

I have never had this happen to me in this car before. 93' 300E.


Here in Atlanta it just started getting cold, about low and mid 30's yesterday. At startup, I always turn the key to the accessory postion for a few seconds, let fuel pumps engage, then crank engine. Upon doing so, i got a little resistance, as if the battery were low on cranking amps, it may be, then when car started, it immediately revved up to maybe 2,200+ rpm's briefly, then settled into its idle warm up mode. Did it yesterday morning, evening, and this morning.

Other than that, everything else is fine.

What should I look at?
-battery cranking power
-starter
-some sort of idle issue
-fuel pumps

FQ

Just wondering if it is the start of something.

sounds like your battery is dying. My (now sold) E320 acted the same way until I replaced the battery.

Roger that.

I will have it checked tomorrow.

FQ

03/95-2 M104 WITH HFM INJECTION SYSTEM


In case of customer complaints of high idle (approximately >2200 rpm) for a very short period of time (< 1 second) immediately after cold start, an updated EA/Idle control unit is available from our PDCs. The updated control units can be identified by a software production date of "SW 43/94" and higher stamped on the housing in the area of the barcode label. The following control unit part numbers are affected:

Electronic Accelerator Control Units

Part No. 124 545 65 32 - E320
129 545 05 32 - SL320
140 545 49 32 - S320
202 545 01 32 - C280

Idle Control Units

Part No. 124 545 55 32 - E320
129 545 19 32 - SL320
140 545 52 32 - S320
202 545 43 32 - C280

Zafar,
That is exactly my symptoms.

So where do I locate the housing with the barcode label?

Do both parts get replaced? EA/IU Or are they independent?

What else do these parts do? Is it an immediate fix i should do?

Any help is appreciated.

Thanks
FQ