[Anzir]

A few weeks ago, I posted about problems with hesitation in the morning on a cold start that would go away after 1/2 mile of driving. It finally got to the point where my SES light came on and I pulled the Peake reader to get oodles of codes, all mainly pointing to an MAFS problem (all sorts of misfires on warm-up as well). I had cleaned them earlier with the method provided on this board, but I guess that wasn't enough (hopefully it didn't foul them more!).

I took it to Continental Imports over here (BMWCCA recommended) and they ran tests to make sure it wasn't a catalytic converter problem.. and sure enough it was the MAFS. They gave me two choices.. replace the MAFS at $350 or something per sensor, or replace the capsules (Bosch OEM parts.. can't do this at a dealer) for $150 each. He gave me the same warranty on both options, and said there was no reason to replace the full sensors. When he called me, he said that the new capsules had already been installed in my car and the difference was "night and day." There were also crankcase ventilation system hoses that were fouled by oil and were cracked.. one of them had split in two.

They've had my car for two days since they've been waiting for the hoses to come in, but it should be back this evening. I'll definitely be posting back here with impressions and part numbers as I can get them.

 

[Stickman]

Thank you for sharing your experiences with us. Please let us know what the outcome is - especially if not replacing the MAFS works out.
Good Luck!
Alfred

 

[100%Cocoa]

Sounds like you'll be having a lot of fun in the next couple of days...!

Do you, or anybody else for that matter, know the Bosch part no.s for the modules?

Cheers,
Barney.

 

[Philip]

replace the capsules (Bosch OEM parts.. can't do this at a dealer) for $150 each.

This is big news if it fixes the MAF failures that everyone has. Please post part number.

 

[Ocean's M5]

Yes, that is a great find about the capsules.

It seeems that it can be a DIY for even a novice...

 

[mottati]

maybe i'm wrong, but i was under the impression that when the dealer replaces a mafs, they're just replacing the "guts" that bolt on with those 2 torx screws, which sounds like you are getting cheaper via the aftermarket. That is good news, can you post the bosch pn, at that price it might be worth replacing them as consumables every 50-60k miles.

This is the only 'working part' of a mafs, so this would be the fix. the rest is just a plastic housing, no reason to replace that unless it's damaged

Thanks!
Mike

 

[Beamer_usa]

Keep us posted, let us know how it turns out.

 

[bmwusa]

Thanks for the info, Josh

 

[OldRanger]

.. replace the MAFS at $350 or something per sensor, or replace the capsules (Bosch OEM parts.. can't do this at a dealer) for $150 each..

Very interesting option for the MAFS problems. My car has 59,000 miles. I finally took mine in this week (under CPO) for low power. I did this after I saw my low liters/hour figures at wide open throttle. (I followed the test outlined in one of the recent MAFS threads). Those measurements reinforced my other observations that were more "seat of the pants"

During their diagnosis, the dealership technician decided to change spark plugs and possibly even the coils (the SA couldn't discern from the work order notes at this point). I suggested MAFS yesterday after they'd been at it for two days. (They were following process, I'm sure). Now they've got one MAFS on order. The technicians indicated the improvement was significant.

When the parts come in, I'll post the fuel consumption figures at WOT to compare against my previous posts on the "...how to test your MAFS" thread. Should be interesting.

Oh, by the way...bad service advisors are sometimes a good thing. I asked for a fuel filter change, the SA misread the instructions I left, and I got a free oil and filter change out of it.

 

[DavidS]

Anzir,

Very big thanks for posting this info! Please, try to find out the part number for the Bosch part.

There is more and more indications that you need to replace the MAFs after 50-60k miles, so this will be a huge savings for everyone.

David

 

[DavidS]

OldRanger,

Glad things are being taken care of! Looking forward to the new fuel-flow at WOT data.

David

 

[grp]

I'm another one who would like the part number It's the kind of thing that, given the various problems that we all have (eventually) with MAF's, is a preventative maintenance item at that price.

Regards,

Gary.

OldRanger,

Glad things are being taken care of! Looking forward to the new fuel-flow at WOT data.

David

 

[Anzir]

HOLY COW!

Got the car back yesterday, and WOW! I forgot how much power she's supposed to put out. So here's the story... I went to the service shop to pick up the car, expecting to see one of the plastic components of the MAFS as what they replaced. But, to my surprise, it was what I had initially considered as the whole MAFS unit. I asked him what the difference is in the Bosch and the BMW parts, and he said that the BMW part comes with the housing that goes in the air intake, while the Bosch part is only the capsule/sensor (what has been posted as the MAFS unit in the cleaning threads). The part number is on the sensor itself!

F 00C 2G2 029

Total bill for parts: $308!!!!! That's for 2 units!

Anyway, everything has been solved.. no more stumbling/hesitation on cold (service guy said the car had been running lean on startup) and power wherever I want it. There had been a little hesitation in 2nd gear when I would power into a turn and I thought that might have had to do with the diff, but it was the MAFS as well. The beast is back!!

Any questions on the part, just call Chuck at Continental Imports at 352-377-6604. He said he'd be more than willing to help anyone out who has questions! If anyone is in the Gainesville area, I would definitely recommend them, albeit they put a good amount of miles on my car with the diagnosis and testing of new parts, but I'm still pleased as punch. They give a good amount of detail as to what is tested, what they are looking at.. 1000% better than any dealership I've been to. And highly competent at that.

 

[DavidS]

Thanks for bringing this info, Anzir!!! Very glad your car is back to its true self!

Now that you have brand new MAFs on the car, can I ask a favour of you?

In order for others to be able to quantify how well the MAFs on their cars work, data from as many factory-new MAFs as possible is needed as a baseline for comparison.

Would you like to perform a DIY MAF / fuel-flow test as described in

http://www.m5board.com/vbulletin/showthread.php?t=54788

and post the result, with details on what fuel, air temperature, and if possible athmospheric pressure and humidity as well, please?

Best Regs,

David

 

[jjc1843]

maybe i'm wrong, but i was under the impression that when the dealer replaces a mafs, they're just replacing the "guts" that bolt on with those 2 torx screws, which sounds like you are getting cheaper via the aftermarket. That is good news, can you post the bosch pn, at that price it might be worth replacing them as consumables every 50-60k miles.

This is the only 'working part' of a mafs, so this would be the fix. the rest is just a plastic housing, no reason to replace that unless it's damaged

Thanks!
Mike

Mike:

The BMW ETK I have shows the MAF as a complete housing and sensor, not just the sensor. It won't let you break it down further. (Sensor Only). It would make alot more sense the other way.

 

[bmwusa]

Glad to hear you are up and running again, thanks for sharing the info, Josh

 

[M-Fünf]

What a waste! Replace the whole housing for a part that can be replaced separately?
I wonder if BMW buys that as an assembly from a subcontractor...If that is the case, I can see why it's one "part". It would cost them more to separate the MAF from the housing, and they'd have hundreds of housings laying about.

Thanks for the info on the Bosch part number!!!

:cheers:

 

[lwebb12]

Re: HOLY COW!

Got the car back yesterday, and WOW! I forgot how much power she's supposed to put out. So here's the story... I went to the service shop to pick up the car, expecting to see one of the plastic components of the MAFS as what they replaced. But, to my surprise, it was what I had initially considered as the whole MAFS unit. I asked him what the difference is in the Bosch and the BMW parts, and he said that the BMW part comes with the housing that goes in the air intake, while the Bosch part is only the capsule/sensor (what has been posted as the MAFS unit in the cleaning threads). The part number is on the sensor itself!

F 00C 2G2 029

Total bill for parts: $308!!!!! That's for 2 units!

Anyway, everything has been solved.. no more stumbling/hesitation on cold (service guy said the car had been running lean on startup) and power wherever I want it. There had been a little hesitation in 2nd gear when I would power into a turn and I thought that might have had to do with the diff, but it was the MAFS as well. The beast is back!!

Any questions on the part, just call Chuck at Continental Imports at 352-377-6604. He said he'd be more than willing to help anyone out who has questions! If anyone is in the Gainesville area, I would definitely recommend them, albeit they put a good amount of miles on my car with the diagnosis and testing of new parts, but I'm still pleased as punch. They give a good amount of detail as to what is tested, what they are looking at.. 1000% better than any dealership I've been to. And highly competent at that.

How did your shop get those parts?

 

[s62fan]

Re: HOLY COW!

Got the car back yesterday, and WOW! I forgot how much power she's supposed to put out. So here's the story... I went to the service shop to pick up the car, expecting to see one of the plastic components of the MAFS as what they replaced. But, to my surprise, it was what I had initially considered as the whole MAFS unit. I asked him what the difference is in the Bosch and the BMW parts, and he said that the BMW part comes with the housing that goes in the air intake, while the Bosch part is only the capsule/sensor (what has been posted as the MAFS unit in the cleaning threads). The part number is on the sensor itself!

F 00C 2G2 029

Total bill for parts: $308!!!!! That's for 2 units!

Anyway, everything has been solved.. no more stumbling/hesitation on cold (service guy said the car had been running lean on startup) and power wherever I want it. There had been a little hesitation in 2nd gear when I would power into a turn and I thought that might have had to do with the diff, but it was the MAFS as well. The beast is back!!

Any questions on the part, just call Chuck at Continental Imports at 352-377-6604. He said he'd be more than willing to help anyone out who has questions! If anyone is in the Gainesville area, I would definitely recommend them, albeit they put a good amount of miles on my car with the diagnosis and testing of new parts, but I'm still pleased as punch. They give a good amount of detail as to what is tested, what they are looking at.. 1000% better than any dealership I've been to. And highly competent at that.

Anzir:

Thank you for posting this info. It will surely save many members mucho $$$ down the road. MAF replacement should be included in major tune ups, along with O2 sensors. It's nice to find an economical replacement for a ridiculously overpriced part.

Eric

 

[Anzir]

Re: HOLY COW!

How did your shop get those parts?

They are an authorized Bosch dealer. Give them a call if you have any questions!