Date registered: Mar 2005
Vehicle: '01-E320 & 02-ST2
Location: John 15:18-19
Mentioned: 0 Post(s)
Quoted: 35 Post(s)
Beard, you're likely to get better advice in the R129 forum as that is specific to your car.
That said, both of the C codes relate to play in the steering column that causes the steering angle sensor to lose memory. That certainly sounds related to the work your mechanic did. Did you also check for codes before the work?
The MAF (mass airflow sensor, aka air mass sensor and a few others) measures the volume of air being drawn into the engine and sends that information to the ECU, which then adds fuel based upon that volume of air, engine load, temperature, throttle position and other relevant data. The MAF on your car also incorporates the IAT (intake air temp sensor) which is separate on some cars. This is also critical information for proper operation.
Bottom line, if your MAF is bad, you need to change it. You didn't mention which code(s) you got that led you to the MAF, but if you're upwards of 80K miles it's possibly done. Do yourself a favor and purchase a genuine bosch MAF assembly from a trusted vendor, avoid ebay inserts, etc. If they don't work properly (though they may turn off the light) they will not properly regulate fuel mixture, which among other things can ruin your cats, which are really costly.
Hope that helps.
Good luck and welcome aboard.
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