New Maf, car won't run

[Mcdiver]

I installed my new Siemens/VDO Maf today, when I tried to start the car, it would not stay running. Put the old Maf in, car runs. Put new Maf in, car don't run. You get the picture. I called the supplier who told me I needed to reset adaptions.

Anyone have this kind of expirence when replacing the Maf?

[Mach540]

That does not sound right. I would think it should at least run, if a little bad, and eventually reconfigure itself. That's the whole purpose of adaptations.

[JimLev]

Sounds like BS to me, I've swapped in good and bad MAF's in the past, never had to reset adaptations.
Try starting it with the MAF unplugged, it should start right up.

[Msport540]

agreed with above, changed out my MAF not to long ago and I just removed the old, installed the new and started her up with no issues what so ever.

[ImTheDevil]

agreed with above, changed out my MAF not to long ago and I just removed the old, installed the new and started her up with no issues what so ever.

As it should be. The DME should see readings from a good MAF and run properly without having to adapt beyond any minimal changes. It may have learned to "expect" a certain range of readings from the old one and had to alter itself based on new MAF readings but even that seems like a stretch and shouldn't take more than a couple miles if anything.

[gmak]

I bought a VDO Siemens MAF for my 1998 528i. Wound up with a CEL. It seems the new MAF was bad. My Indy said that they are seeing a lot of this over the last few years (name brand parts that are 'bad').

Swapped back in the old MAF - no more problem. Sent the VDO back to Germany and they sent me a new one (or the old one 'fixed'). Put it in, and it worked fine.

[m735is]

Do you get a CEL with the new MAF?

I got mine for my 99 528i from AutohausAZ, worked fine out of the box with no adaptation reset needed.

Before I bought a new one, I tried a spare I had. It threw a CEL right away, but the car still ran.

[Mach540]

Do you have a scanner that will tell you what the MAF is reporting?

[Mcdiver]

Do you have a scanner that will tell you what the MAF is reporting?

No, but did the whole reset thing, disconnected the battery for an hour ( used hazards to drain system of all power), same problem. Oembimmerparts overnighting a new unit.

BBA called and reported no errors on my module, that will arrive tomorrow as well. Now to figure out the transmission light. No errors reported, but it is on.

[geargrinder]

Yeah maybe maybe the adaptations could be so whacked off that it wouldn't run but i think unlikely... If adaptations are that extreme then you'd prob have a CEL all the time.

And the battery reset thing is BS for this purpose, totally wasting your time. Thats for cars from like 1992. Non-volatile memory is in most every ecu since about the 90's. Need a proper software clear adaptations, or, to be able to run it kong enough to re-adapt. The only thing i am not sure is maybe if you run the motor w MAF disconnected if then throwing the MAF code might trigger adaptation reset when you plug it back in. it might. Never tried it to see.

Confused by "dont have scanner" + "transmission light" + "no errors reported". Did you read codes or not read codes?There is zero way you have a light on w/o a code... Really more time wastage to diddle around w any of this without pulling codes. Its just shooting in the dark and speculation when you might have exact diagnosis info ready to tell you what the deal is. Get buddied up w somebody w a computer & diag software, or buy a Carly for your smartphone or whatever... Life will be WAY easier... And dont waste time with some generic walmart scanner that just gives crappy "p" codes either, a BMW specific tool is way better, and w the smartphone options its < $150 to get setup...

[Mcdiver]

Yeah maybe maybe the adaptations could be so whacked off that it wouldn't run but i think unlikely... If adaptations are that extreme then you'd prob have a CEL all the time.

And the battery reset thing is BS for this purpose, totally wasting your time. Thats for cars from like 1992. Non-volatile memory is in most every ecu since about the 90's. Need a proper software clear adaptations, or, to be able to run it kong enough to re-adapt. The only thing i am not sure is maybe if you run the motor w MAF disconnected if then throwing the MAF code might trigger adaptation reset when you plug it back in. it might. Never tried it to see.

Confused by "dont have scanner" + "transmission light" + "no errors reported". Did you read codes or not read codes?There is zero way you have a light on w/o a code... Really more time wastage to diddle around w any of this without pulling codes. Its just shooting in the dark and speculation when you might have exact diagnosis info ready to tell you what the deal is. Get buddied up w somebody w a computer & diag software, or buy a Carly for your smartphone or whatever... Life will be WAY easier... And dont waste time with some generic walmart scanner that just gives crappy "p" codes either, a BMW specific tool is way better, and w the smartphone options its < $150 to get setup...

I have a peake scanner. I currently have 2 codes, bad Maf, communication time out with abs module. Module will come in today from BBA reman. New Maf should arrive today. We will see in the am. I will have a snap on computer tomorrow just in case there are more issues.

[m735is]

Don't worry too much about the tranny light, it popped up when I tried my "unknown quality" MAF that came on a parts car. It disappeared when I swapped back my original MAF.

[ViolinARC]

MAF should be plug-n-play...no need to reset adaptations. :confused