I am having a new air mass meter shipped. Is this something an average home mechanic can replace?

Will the "check engine" light eventually go out if the AMM was the problem and changed? (A Mercedes dealer diagnosed the problem, but I didn't want to spend 3 times the money for the part)

Best,
Karl, 1998 E430 Sport

Yes the light will go out eventually if the repair fixes the problems. Properly done the adaptations should be cleared. Untill the adaptations readapt I would avoid any energetic driving. It is possible to set other fault codes till it does readapt. It will readapt in probably ten miles enough for driving purposes. What will happen is that because of the old AMM the car will run too rich (they all fail lean on the late style AMM) as it will have the correct sensor reading plus the correction used to run with the old unit.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

OK, Steve.

Thanks for the information.

Best,
Karl

here is a document that will help you with your repairs, let me know if it was useful, it can be printed for use during the repair

I did this job on a 97 c230. It shouldn't take more than 10 minutes. You can clear the check engine light it you have a code reader. I just disconnected the battery for a minute. If you do that make sure you have your radio code handy.

Carson356,

Terrific. I have printed the instructions out. However, just looking at the engine it seems that the airmass sensor can be replaced without removing the air intake pipe.

Best again,
Karl

I have a '99 C230 with apparent mass flow meter problems. I've owned the car only since 50K miles and I'm now replacing the mass flow meter for a second time at 77K (first was at about 65K). I believe the meter failure is a result of an oily mist circulating through to contaminate the sensor. I think this is usual, but that mist may be a bit rich on my car and the sensor failure may only be symptomatic. Cannot anyone offer a suggestion on what is causing / creating this failure?

Make sure you have tamper proof torx sockets if you are just replacing the insert like Bosch provides for about $ 77.00.

You can use needle nose pliers to grip the torx screws form the outside and muscle them out.

The Bosch inserts provide you with new phillips screws to back in with.

Also make sure you replace the engine air filter and take the air box out and clean all the debris out.

You can replace the mass airflow sensors all day long, but if your engine air filter is is bad shape, it can trash your new air mass sensor within days.

Been there done that, always replace the engine air filter too, always, did I say always?

Clean the dust and debris out of the airbox, and make sure you don't get any dirt down the inlet tube in the process.
I cover the tube opening with a lint free towel while exposing it during repairs.

John.