Hi everyone , I'm the latest new guy to show up with a problem and I've searched for similar issues but haven't come up with anything . My C230 has 46k on it and until now , hasn't given a single problem . However last weekend I drove down to NYC through ~ 5 hours of rain and my CEL came on . The car continued to run fine and since it was just lit and not blinking , assumed it was a soft code for something like an 02 sensor or was a glitch caused from all the rain as my Discovery , also with Prince of Darkness electrics , does funny things when soaked so I figured that was a possibility . I had no issues at all on the drive back and used an OBDII reader to check for codes but only came up with an E . I left the gas cap off my Disco to make it throw a code so I could check that the reader was working - and it was . Just for the hell of it , I took the Benz for a drive and it started running extremely rough - would not rev over 4500 RPM's etc and the CEL flashed so I pulled over and shut the car off - it was the first time that anything seemed *wrong* . After waiting a minute to collect my thoughts and pull out my AAA card , I tried to start it and though the CEL remained steadily lit , it did not flash and ran as fine as it ever does all the way home . The reader was still saying error so I thought that perhaps resetting the computer might do something so I disconnected the terminal and when I reconnected it , had a great running car with no CEL - however , 20 miles later I had the same severe loss of power - rough running experience - with the CEL lit , but not blinking and still with no codes !


If someone has any experience with this one , I'd be grateful for any advice . I guess I'm going to have to bite the bullet and take it for a service but I live on an island and the nearest dealer is a couple hours away so I can't just pop on over . Please don't tell me it's the ECU itself or at least if you do , please tell me that they're really cheap from MB !

thanks ,

joel

 

Our cars are made so that if a sensor throws a major fault code to the computer, the cars go into "limp home mode" where the car runs on 2 cylinders (for a 230). Shutting down the cars for a few min often re-sets the computer to run "normal", but the CEL stays on to irritate you to go get it checked-out by a mecanic who can read the codes and re-set the CEL. I don't know why your OBDII is not reading a fault code, unless for some reason it is not 100% compatable with MB's.

From what I read on the forum and from my experience with this happening to my C-220 often it is the mass airflow sensor (MAS) or an Oxygen sensor that goes out to cause this.

 

Your scanner has to be DIN - Daimler Chrysler compatable. Not Ford or GM. Some are all 3, those will also work. What were you using? Flashing CEL means that the ECM thinks that your doing serious damage, engine miss, Cat overheating,... Good luck

 

If you have the code reader instructions, read what E means. It's probly not reading your MB at all for some reason. Most scanner need to be setup with the brand of your car before you can read it.

If you still can figure out how to read the code, get to the dealer or have a local shop do it.

 

Thanks guys . I hadn't thought about the reader not working on MB's . I've got it scheduled to go in next week so it's TV dinners till then in preparation for the bill .

 

Hungry man TV dinners are the best bang for the buck...

 

For future crises , which model OBD II reader should I get to work with it ?