I am trying to find out what code my CE light is hiding. The light comes on during idle and the enging starts to miss. Then the engine runs fine at hwy speeds and the light may go out at that point.

I understand from reading other posts that I may be able to figure this out through the round 9 pin connector on the drivers side. My questions are:

Is this the proper connector for the '89 with a 103.940 engine?

How do I use an analog or digital meter to find the code?

What are the codes for this engine? I have found a dozen for a 1990 and up but not the '89.


I wish I could find this in the maintenance CDs, but no luck so far.....

Thanks for any help on this!

__________________
John

1995 E320 - 115kmi+ Smoke Silver/Cream (Wife's Wagon)
1989 260E - 195kmi+ Black/Grey (My Panther)
1984 300D - 242kmi+ Black/Palomino (Retired)

Hey, does anybody have the proper procedure and codes for my '89?

Thanks

__________________
John

1995 E320 - 115kmi+ Smoke Silver/Cream (Wife's Wagon)
1989 260E - 195kmi+ Black/Grey (My Panther)
1984 300D - 242kmi+ Black/Palomino (Retired)

It usually means your O2 sensor has failed.

__________________
2008 E350 4matic / Black/Anthracite

------------------------------------
Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black

You will need a DMM with a duty cycle function. Connect it between pin 3 of that connector and ground with engine off, key on. If it reads a constant multiple of 10% that is your code. You will be able to go to the factory CD and decipher the code.

The most common code will indeed by the O2 sensor, but it may very well not be the sensor itself. There is a connector under the right side front floor mat that often comes loose or needs attention.

Good luck,

As Larry states the O2 sensor code MOST often isn't the sensor itself. The code sets when the activity of the code is not happening. I had one old 300e with such a code just due to lack of power to the heater circuit of the sensor. It wasn't getting hot quick enough and would cool off at idle.

Any mixture problem (or misadjustment) that overwhelms the ability of the system to adapt will leave the sensor pegged. This is the Number one problem!

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Thanks guys, I appreciate it!

John

__________________
John

1995 E320 - 115kmi+ Smoke Silver/Cream (Wife's Wagon)
1989 260E - 195kmi+ Black/Grey (My Panther)
1984 300D - 242kmi+ Black/Palomino (Retired)