kskane

Hi Guys, I have a question it is pretty simple but I don't know the answer. Can the car run without a MAF sensor i.e. if I disconnect or remove the MAF Sensor from the car altogether, should I be able to feel any difference in the car running? Basically, I removed my MAF sensor today to spray it with CRC cleaner and in the middle I thought why not make life easier and try to start the car anyways, and it did start without any issue. So, does that mean the MAF Sensor is dead, or is that normal behaviour?

Second question, on 2004 E60 M54 how many MAF Sensor's are there? I found only one so far on my car and hoping that is right, but wanted to confirm as I heard on M5's there are two of them.

Third questions, if the sensor needs to be changed, do I need any coding done from the $tealer?

turboawd

i would not drive the car without the maf. the maf helps calculate how much fuel to inject.

roskinc

far as i know theirs only one. mine went bad recently and some symptoms where bad accelerations, idling was horrible and i would get errors and my car would go into limp mode occasionally.

replaced it, runs perfect now.

kskane

Okay, so if by removing MAF, the car idle as normal (slightly rough), how can I test the MAF? Removing it throws error, connecting it back removes the error, but physically in idle there is no difference with MAF present or not. Is there a better to test it?

Maini

The MAF has been put in there for a reason!! Please do not remove it.. Please google the exact working of a MAF and you will realize it is very important function. The very fact that without a MAF your car throws errors means that it needs it and your MAF is working. The idling aspect not changing is unscientific and not relevant.

kskane

Thanks Maini, and I did not meant to remove the MAF altogether, it was only for testing purpose.

Any ideas on testing a MAF Sensor using INPA maybe?

turboawd

what are you trying to solve? what issues are you having?

kskane

This https://5series.net/forums/e60-discu...erious-132821/

kskane

I found the following sections in the INPA to read the air flow, not sure what it means or does.

From the different pictures and my testing with INPA what I can see is below;
MAF Sensor Voltage at ignition (engine off) is 0.41V with 4kg/h and Air mass = 1.1 g/sec
MAF Sensor Voltage at engine on is 1.4V which comes down on 1.2V with 13kg/h and Air mass = 3.4 g/sec

From the reading above, and the images, can someone help me to diagnose how to test if the MAF sensor is functioning fine.

turboawd

so just vibe at idle. run good other than that? i dont think i'd suspect the maf as being the culprit. bad maf would cause engine to rev up or just die.