1991 300E - runs rough, can she fix it? - PeachParts Mercedes-Benz Forum

mbzr4ever · #1 03-04-2014, 06:01 PM

Quote:

Originally Posted by lorainfurniture

First thing to address is the check engine light. Most times on these cars the only thing to trip the light is the o2 sensor. The car is likely running very rich or lean.

Next is to give a full tune up. Cap, rotor, wires and plugs. I would check the vacuum as well. You should have a min of 12hg, ideally 15-16 at idle.

That hose that connects from the airbox to the valve cover won't help your running issues, but should be addressed anyway.

Lorainfurniture,

Search can't seem to handle "o2" because it is too short, is there something else I can search by? Maybe the word oxygen sensor or ?

lorainfurniture · #2 03-04-2014, 09:56 PM

Quote:

Originally Posted by mbzr4ever

Lorainfurniture,

Search can't seem to handle "o2" because it is too short, is there something else I can search by? Maybe the word oxygen sensor or ?

Try google search "300e check engine light" or "w124 check engine light"

I don't remember where I read it, but it made sense when I read it. The check engine light is always emissions related (please someone correct me if I'm wrong), And the o2 sensor is about the only electronic emissions device on the car.