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Quote:

Originally Posted by waffles (Post 826991)

Excellent ill give that a try.
Should i buy a Bosch MAF or Geniune BMW? Is there much of a difference?
Im probably gonna source it from ecstuning.com as I have dealt with them before.
Also,
Just today when i turned the car on, the outside temp reading changed from Celsius to Fahrenheit. Weird. Also, later today the engine light came back on. Its really starting become annoying.

Should I disconnect the battery for 30 mins to reset everything?

Any takers?

If the Service Engine Light has come one then you'll need to have the codes read. Even if the SEL is no longer illuminated the computer stores codes for quite some time so there should be some stored.

Quote:

Originally Posted by o. l. t. (Post 826913)

This is because your sensors have been reset. If it doesn't clear up after a few days of driving you will likely have to replace the MAF. When the car ECU hasn't been reset it runs off a cache file of information it uses as a baseline and only changes mildly during driving. With the ECU reset from the battery change you can always find a bad MAF if the truck does what you are saying and doesn't come back around after a few days of learning the MAF again. Learned that the hard way on my Mercedes CLK 430. I have made this bet with people and won every time.

I'd be surprised to learn there's a cache of MAF information stored in the ECU. It's my understanding the ECU uses information provided by the MAF or default parameters if it deems the MAF to have failed.

An easy way to test if the MAF is causing the problem described is to disconnect it. This will cause the ECU to use the default parameters which should eliminate the described problem if the MAF is at fault. Doing so will illuminate the Service Engine Light but it will turn off once the MAF has been reconnected.