w201 C36 rough idle

[ctscna1]

I just bought a C36 and it got a check engine light for MAF also the idle is running rough. I bought a new MAF from Dealer but when i installed, it was sag/cut out to rev higher rpm. So, i put the old MAF back and it run better. . Sometime the car idle fluctuating between 500-1500 rmp? Do u guys know what wrong with it? What's the most common problem on this car?

Thank you

[duxthe1]

The problem may be with the harness for the air flow sensor and not the sensor itself. A lot of mid nineties 104 engines are plagued with harness problems.

[OzC36]

When installing a new MAF they say it is recommended to reset the ECU to basic factory settings by disconnecting the car battery for 5-10 minutes (the ECU settings will have been messed up by the bad MAF).

Then start the car and let it run for about 5-10 minutes at idle to allow the ECU recalibrate to the new MAF. Then take the car for a drive and excercise the engine over the complete RPM range. The complete calibration will be done over a few runs.

Yes, the engine will run rough with a perfectly good brand new MAF when you first start it if you don't reset the ECU...

[TMAllison]

What year is it...

The MAF will adapt itself withn 50 miles of driving as well which may not help if it is so rough running as not to be driven.

[ctscna1]

The car is 95. I have tried to install the new MAF and disconnected the battery for 15 minutes to reset the computer but same as the result before, the car can't rev up to 2000 rpm(seem to be fuel cut out) even WOT. I can't drive the vehicle unless i used back the old MAF, the check engine light(P0101) will come back around 30 miles of driving once i had clear the code with the old MAF.

[OzC36]

Part number 0280217500 is the correct part number for your 1995 W202 C36. The OEM part is Bosch. I would strongly recommend that you only use Bosch rather than after-market brands.

First of all, check for the correct part number. If the part number is correct and your car doesn't run, then return the new MAF to the dealer for refund or replacement under warranty.

If your car runs with an old MAF, but refuses to run with a new MAF, then the new MAF is stuffed.

See below for alternative source for MAF:

http://www.***************/search/product.aspx?sid=ode3sk45idas3h555xaidm55&makeid=800016@Mercedes&modelid=1195501@C36&year=1995&cid=22@Fuel%20%26%20Air%20System&gid=5068@Air%20Mass%20Sensor