Mako

Doesn't the MAF sensors which is basically a resistance heat up after shuting down the car? The dirt on the sensor vapourizes. Cleaing should be therefore pointless.

blackonblack:
Does this idling issue happen always. To me it happens sometimes for a few minutes and then disappears again.

blackonblack

Since I have cleaned the throttle body and overhead, the idle is always and constantly at around 1,100 - 1,200 RPM. I have also noticed that it drives a little differently now, it's not as smooth, and shifts very strangely.

Mako

How did you clean the MAF, you are only supposed to spray the dirty off with a brake cleaner and then maybe carefully dry it with presurized air. Dont touch the sensor element.

I also cleaned the throttle body with brake cleaner.

Disconect the battery wait a few minutes and connect it again. maybe that helps resetting the idle.

It should be at 500 with the AC compressor off and at 700 with compressor on.

dawid_w

Sounds like MAF sensor is gone. How did you clean it?

I still think that your problem is related to lack of pressure in the intake (pressure sensor, cracked vent hose or leaking intake steel gasket)

blackonblack

I cleaned the MAF sensor using non-chlorinated brake cleaner. I sprayed a few bursts on the contacts and let it try. What's it supposed to do without the MAF sensor connected? If I disconnected the car barely stays running and dies right away (without giving it a bunch of gas)


I also read in the BMW dealership notes that they "adjusted the minimum valve lift from, .3 mm to .8 mm to help the idle speed" . This was before I cleaned my MAF sensor. Could this have something to do with the high RPM?

I tried disconnecting the battery and it's still the same.

I took it to auto zone and the diagnostic code was p0507 Idle Air Control System RPM Higher Than Expected.

I am planning to replace the differential / pressure sensor. It seems like a harder job since it's in the rear of the manifold I'm thinking that I'll have to take the whole manifold out?

turboawd

stores sell a specific maf sensor cleaner. i'm not sure if brake cleaner was a good idea.

double check and make sure you connected everything good, and that the intake tubes are seated well. a vacuum leak after the maf sensor, will affect the idle.

denissm

This is usually done, when some or many or all valves show values that are higher than normal and that is a case of valvetronic nearing the end of its lifecycle.
Usually this procedure is done before selling the care, the value of valves are then again normal.

I ask that you keep in mind that practically nothing changes in a cars performance when this procedure is done (except it loosing a very small amount of power at some times and fuel mileage lowering a bit).

blackonblack

I used brake cleaner because I read that non-chlorinated brake cleaner was okay to use since it left no residue.

I cleaned it again using MAF cleaner. I double checked all the tubes and seals, it seems to be fine.

Is it possible that I ruined the sensor by using the brake cleaner?

The car runs at a constant 1,200 RPM after it warms up. When the MAF sensor is disconnected, it runs (not real smoothly) at around 700 RPM. Does this indicate anything? Such as the MAF being bad?

blackonblack

Here is a video of the car running with & without the MAF sensor.
hhttp://www.youtube.com/watch?v=JdOMYMoYpyM

Mako

Hi
did you clean the contacts of the connector or the sensor element in the pipe?
I did clean the sensor element the same way you did and nothing changed.

Look here:

http://www.aa1car.com/library/maf_sensor_ford.gif

Your are also supposed to take out the MAF by including the part of the intake pipe and not the sensor alone.

Disconnect the battery, then plug in the MAF and then connect the battery again. Delete the fault memory of the car and then start it up

If it still doesnt work then get a new MAF or try to get someone with a BMW N62 engine to swap it for a test.