Need help with Check Engine Light
Thread Starter
Newbie
Joined: Feb 2006
Posts: 8
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Need help with Check Engine Light
The check engine light is on on my 1991 300SE. How do you read the codes out of the ECU and what equipment do I need. I'm assuming this car is pre-OBD so a scanner won't work. I'm new to MB but I do have a lot of experience working with fuel-injected cars. Any help would be greatly appreciated. Thanks!
Thread Starter
Newbie
Joined: Feb 2006
Posts: 8
Likes: 0
It's not a vacuum leak. I generally work on my own cars (I used to build turbo 4-cylinder engines and old american V8s). German engineering is soooooo different than what I'm used to. I figured out how to pull the codes and reset them, but I keep getting the light back on for the same thing. Apparently it's code 9 and 17 (O2 sensor and EHA voltage). I replaced the overload voltage relay to no avail. Please anyone help! 
