Check Engine light on 94 C280
 

Well my check engine light came on again. It came on about 8 months ago, and I had one of the O2 sensors replaced, the one about half way down the exhaust after the catalytic converter. The check engine light disappeared after I disconnected and reconnected the battery.


so it came on again yesterday. Is there a way to tell if it is the primary or secondary O2 sensor, or how to access the failure codes?

I know in some beamers, you can turn the key, tap the breaks, and depending on how many blinks the light blinks it identifies an error code.


do we have something similar on the 90's model mb's, or is it only acccessible thru a computer?


as always any help is gratefully appreciated.

oh yeah ...some other vitals
 

The temperature is normal during running, 80C, the car sounds completely normal, pick up is normal, smells are normal. There is no oil pressure guage, like the 280 E, RPMs seems normal for standard driving.

The coolant level is fine

no other lights are on.

You need to pull codes on that car- go to a shop that knows how.

I agree...and if you have an Auto-Zone nearby, they do it free ..
List the codes when you get them

Do not assume it is 02 , there are many,many code detected faults that will trip the CE lamp..

Friend has '96 C280, CE light on, pulled codes P0101 and P1170. Any thoughts as how he might proceed?


2000 E320
Brilliant Silver Ash

..that a typo for P0170 ???????????????

got my codes pulled - EGR issue
 

the garage told me it was/is an "EGR" issue. As I recall the EGR is recirculation of the exhaust to cool the cylinders, or something like this.


They reset the computer to extinguish the CE lamp and it has not come back.



They said that if the problem was temporary the light should have gone off by itself. However it has not come back on since they reset it and we have driven about 500 miles so far.

any comments that would explain this behavior?

thanks

Your chassis had an EGR issue upgrade for sticking egr valve shaft.
The part has been changed to one with a smaller diameter shaft.
Also had an issue with the egr return tube blocking up with carbon.
As your problem seems intermiitent , I would look at the valve .
There is a simple test for both
Try archieves 'EGR TSB'