CEL and Hesitation on C230 - PeachParts Mercedes-Benz Forum

roadsession · #1 11-27-2003, 01:53 PM

Hello,
My ML remains rock solid, but now my 97 C230 is giving strange problems.

The check engine light is on and the car is extremely hesitant and drives like it can't find the right gear or something.

I've read that it could be the transmission itself, or a bad battery.
Would a bad MAF cause the same symptoms?

Thanks

blackmercedes · #2 11-27-2003, 04:47 PM

It could be many, many, many things. You'll have to have the codes read and a proper diagnosis preformed. You can go to Auto Zone and they'll read the codes, but be warned that this probably won't highlight the exact problem. You'll need to be able to investigate further.

As an example, a misfire code could be a faulty/worn plug, plug wire, etc. The tranny might be giving some fits, mine did and it felt all the world like a bad misfire or fuel starvation problem.

Get thee codes read.

joe p · #3 11-28-2003, 08:12 AM

What he said.

Likely culprits providing it makes it to top gear.

Coil, resistor tip, plug, wire, MAS, vacuum leak or wiring harness.

If it "sticks" in second or third.

Speed sensors in conductor plate, rear abs wheel speed sensor, wiring harness, shifter posistion switch or atm leakage into the atm connector "wicking" trans oil into the etc.6 control unit.

Joe

roadsession · #4 11-28-2003, 03:46 PM

Quote:

Originally posted by joe p
What he said.

Likely culprits providing it makes it to top gear.

Coil, resistor tip, plug, wire, MAS, vacuum leak or wiring harness.

Joe

Joe, the car shifts all the way up to top gear...It's just very sluggish and jerky doing it... the Check engine light had come on, and the code reveals a left feul bank problem which leads to the MAS.

My question is, does a bad MAS make the car all slugglish like this and obviously affect transmission shift points - right ? (crossing fingers)

blackmercedes · #5 11-28-2003, 05:07 PM

Yes, the symptoms do sound like the Air Mass Meter is gone. Has the CE light been on for a while?

Did you get codes P0170 and P0171?

roadsession · #6 12-14-2003, 08:45 PM

Ok,
Got the Mass Air Flow Sensor from Fastlane (mercedesshop - THANKS PHIL!!- The dealer wanted $500 and I got it from him for $300) and in 5 minutes swapped out the old one.

The car is PERFECT.

The whole problem was due to the MAF sensor.

The fault code indicated 02 sensor, but as it turns out a bad enough MAF sensor will set an error code indicating 02 sensor problem as well.

Thanks everyone.