1994 e320 high idle
 

I have a 1994 e320, I had a problem with the idling, it used to rev up and down.... i changed the spark plugs, wires, mass air flow sensor, some vaccuum lines. but now the idle stays high. i tried adjusting it, but it stays the same. in drive its at about 800, and in park it settle at about 1200 or 1300.
it used to be in drive around 500 and park 700.

I read the codes i got:

code 6 in the built in reader
code 8 in pin 8
code 2 in pin 14

any ideas?

I would like to add that during this problem i did play around with the cables adjustments in the engine compartment and at the gas pedal.

SEND me your vin and email so I can send you some documents. I have some good info on your problem ))

wdbea32e1rc114533
lebstyle@hotmail.com
thanks

Have your "throttle actuator" checked.

Check out MENU#24 on my pages for the "ETA" problem. . . those codes point to a failing ETA . . . . or a bad wiring harness. If the W/H hasn't been changed you probably should start there.

i have chekced all the wiring , it is still good. i think the throttle actuator is working properly. b/c i know its working. if it wasnt, the car would be idling up and down. im thinking it something else triggering that.

Check that the cable has a 1/4 slack and that the rug is not bunched up. Both of those will throw Closed Throttle Position code..
also check that the cable is not sticking..

what do u mean by the rug bunched up.

Check around the base of the gas pedal.. See them get extra mats and rugs , along with dirt and sand, etc..that stops the CTP sw from getting closed, just like the throtle cable can..

Does your cruise control work?

This is from a thread I started about a year ago..........


Update: the rest of the story.....

Problem is back, below is description of problem.

Installed rebuilt unit in a 1995 E320 Sedan.
Initially the unit operated correctly, 2 days later, operation became
intermittent. Symptoms are intermittent high idle speed (1400 RPM in park,
1000 RPM in gear) and inoperative cruise control. (either both symptoms are
present, or neither are present. never one without the other) Shutting off
the car and restarting will sometimes cure both problems, but they both
reoccur. Retrieval of stored fault codes (via impulse code reader, not HHT)
consistently yields the following:

Diagnostic module: code 6: Idle speed control inoperative

ECU module: code 8: Idle speed control (ISC) system at upper or lower
control stop

HFM SFI module: code 2: EA/CC/ISC control module (N4/1) or Safety contact
switch (M16/1s1) or Stop lamp
switch or Cruise control switch or Actual value potentiometer or Starter
lock-out/back-up
lamp switch or engine speed signal or vehicle speed signal or closed
throttle position
switch or safety relay in EA/CC/ISC control module

Out of desperation, I replaced the remanufactured unit with a known working
unit pulled from an identical fully functional vehicle. Idle speed/cruise
control now work properly. So far, there is no indication of intermittent
failure.

Returned unit to Beckmann for testing, they confirmed reman unit was defective. (the drive motor was bad)

Hope this story helps someone else........................

Reman . . what??? ETA??

What ECU module???

Tnx for posting that . . .all info is good info.

A suggestion to DTC posters is to use the NAME of the module being read from the PIN. . . . not just the pin. The reason is simple: In a E320 the diag connector's pin layout is different from that of a S500; 16 vs 38 pins. By talking "function", all confustion is eliminated.

I have been noticing also hard shifting in the transmission, and it shifts quickly. you can feel it shift a gear right before you stop.
i am thinking possibly a vaccuum leak might cause it?
i checked the cable, it is pretty free.

I just had a similar issue on my own car (94' E320). The throttle return spring was broken. ;)

where is that located? and what does it look like?
thanks