Xoutpost.com - What the heck is causing this!?!??

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What the heck is causing this!?!??

Okay, I have had this issue for the longest time and I am HOPPING that it truly is caused by a faulty MAF sensor because its just driving me insane.

Recently I had my transmission completely rebuilt and I thought for some reason that it was the cause of the gear getting stuck and causing this but it still is going on after the transmission rebuilt.

Basically I accelerate up til around 20 MPH and then i let go of the GAS and the MPG gets stuck along with the RPM and then you feel like a hard down shift after a few seconds and then RPMs drop and so does the MPG and then the X continues to roll as if all is normal.... Could this be caused by the MAF? If so great because I just cleaned it using CRC MAF SENSOR CLEANER and to be honest I feel no difference. I am going to have it replaced soon and see what happens, other then the MAF is there any other sensor that could cause this?

Update: Currently I have a code, that is not setting off the SES though, I just noticed this myself, 140 - Activation Map Cooling - Assuming its the thermostat I will look into it and have it changed as well now... errrrrrrr

I would think there is something wrong with the tranny or it's sensors.

Is this happening while in sport mode only, or all the time? Also, have you tried "resetting" the transmission by putting the key in position 2 and holding down the gas pedal for like 30-40 seconds? I can't remember exactly at the moment, but this is what got rid of my transfail message after I removed the entire center console.

As for the MAF cleaner stuff, it's a waste of time. The wire inside the MAF works off resistance, and after a while, just like spark plugs, the resistance becomes too high. You simply need to replace it. I'm gonna open a whole can of worms here, but you can use a VW MAF sensor only for around $80 instead of replacing your entire MAF sensor and tube for like $200-$400. If you want, head over to www.m5board.com or the M5 forums on www.bimmerforums.com and search around for the part #. This doesn't work on the 3.0, and as far as I know it'll work on anything from the 4.4-4.8 since M5 guys have 4.9/5.0 engines.

Quote:

Originally Posted by TheKingSim0n (Post 745303)

my 02 4.4i had this started from this. i had SES light on i cant recall what it was i think p0174 and p0171 or something then i bought AM MAF from ebay $70 SES light went off and then the transmission starts to act so i took it to the dealer all they changed was Factory MAF $430 some Dollars and that was it never had any problem with transmission again like you would think MAF and Transmission WHF? thats what i said when i picked up the x from the dealer, but i sold the x in my family its still running strong 190kms. Good Luck.

I had the same issue last week. Replaced MAF from the dealer and seems much better.

Well I am awaiting for the MAF to arrive and then ill reply on if it did the trick...