[Len_Beach]

I removed and cleaned my MAF and MAP sensor a few weeks ago.

I saw around 3-4mpg gain as a result.

I then got INPA up and running again and scanned my error codes and found 3FC0 - Air flow meter - Deviation too high at idle speed.

The error will not clear and is present even when the engine hasn't been started after code clearing.

I've bought a second hand confirmed working MAF and this shows exactly the same code which I find hard to believe.

This leads me to think something else is the issue.

Any thoughts Guys?

[Hoooper]

Need to reset the learned parameters. The computer had adjusted to the dirty maf but now that's its clean the reading is too far from the learned expected value

[Len_Beach]

Originally Posted by Hoooper

Need to reset the learned parameters. The computer had adjusted to the dirty maf but now that's its clean the reading is too far from the learned expected value

Awesome! I had thought that.

So reset engine adaptions?

Is it a similar process to gearbox adaptions?

[Mik325tds]

Fairly simple. In Rheingold select Vehicle management, Service function on the top two rows. Then click your way through 4 layers of selections:
01 Drive > Digitial Diesel Electronics (US version) > adaptations > Air mass flow sensor. Then click "Start search" and on the next screen double click ABL Mass meter.

[Mik325tds]

Originally Posted by Len_Beach

I removed and cleaned my MAF and MAP sensor a few weeks ago.

I saw around 3-4mpg gain as a result.

Len, what cleaner did you use?
Others, is this something we should be doing regularly or is there potential of damaging the sensor?

[shnaggs]

I was always under the impression that cleaning a MAF, even with (MAF cleaner) would destroy the elements.

Maybe that's only for particular MAF's???

[Len_Beach]

Thanks Guys.

I'll download Rheingold and have a crack.

I used an electrical contact cleaner. There are numerous guides online as to how to do this.

It's definitely an issue with the car as my replacement MAF also shows the same code.

[shnaggs]

Maybe you have a short in the harness?

[glitdi]

Originally Posted by Mik325tds

Len, what cleaner did you use?
Others, is this something we should be doing regularly or is there potential of damaging the sensor?

Brake clean is a good one to use, or maf cleaner... Its important to spray in the direction of air flow... Also take the maf off the car, you don't want a intake full of brake clean, maf cleaner when you start it up..
A maf shouldn't get dirty it does but mostly due to moisture and small bits stick to it. Cold air intakes, high flow filters, sacrifice filtering for flow, in my opinion high flow filters are the biggest scam in the auto industry.

[glitdi]

Originally Posted by Len_Beach

I removed and cleaned my MAF and MAP sensor a few weeks ago.

I saw around 3-4mpg gain as a result.

I then got INPA up and running again and scanned my error codes and found 3FC0 - Air flow meter - Deviation too high at idle speed.

The error will not clear and is present even when the engine hasn't been started after code clearing.

I've bought a second hand confirmed working MAF and this shows exactly the same code which I find hard to believe.

This leads me to think something else is the issue.

Any thoughts Guys?

How is the intake? any sludge any cbu? I know that the gummed up intake will cause back pressure and cause the car to see less air volume than is expected, intake leaks can lead to same result.

[Len_Beach]

Originally Posted by shnaggs

Maybe you have a short in the harness?

I'll have a look at the harness once I've reset the adaptations.

[Len_Beach]

Originally Posted by glitdi

How is the intake? any sludge any cbu? I know that the gummed up intake will cause back pressure and cause the car to see less air volume than is expected, intake leaks can lead to same result.

When I cleaned the MAP sensor; it was quite coked up which I think made a difference to the drive.

The car is an N57 so it's a different EGR setup to the M57. When I checked the EGR; it only had a thin film of soot and and a spear of oil.

[jkelsey1]

Originally Posted by glitdi

How is the intake? any sludge any cbu? I know that the gummed up intake will cause back pressure and cause the car to see less air volume than is expected, intake leaks can lead to same result.

My 2010 335d threw code P0101 MAF issue often post 65K mi. until I had CBU cleaned. It has been six months and 6K mi. with no repeat code.

[Len_Beach]

Originally Posted by Mik325tds

Fairly simple. In Rheingold select Vehicle management, Service function on the top two rows. Then click your way through 4 layers of selections:
01 Drive > Digitial Diesel Electronics (US version) > adaptations > Air mass flow sensor. Then click "Start search" and on the next screen double click ABL Mass meter.

Mick; a huge thanks!

After finally sourcing a working copy of Rheingold; I think I've finally managed to clear this fault code.

It couldn't come soon enough as I now have a 480a DPF fault which I believe is due to the MAF fault preventing re-gens.

I'll try the old clear fault code method of it persists.

If anyone has a 3FC0 fault; follow Mick's directions above.

Thanks again Buddy.

[Hoooper]

Originally Posted by Len_Beach

Mick; a huge thanks!

After finally sourcing a working copy of Rheingold; I think I've finally managed to clear this fault code.

It couldn't come soon enough as I now have a 480a DPF fault which I believe is due to the MAF fault preventing re-gens.

I'll try the old clear fault code method of it persists.

If anyone has a 3FC0 fault; follow Mick's directions above.

Thanks again Buddy.

Glad to hear youre back up and running. Can you PM me where you found rheingold? Im thinking I want to get up to speed with that software since ediabas really doesnt do it for me.

[Mik325tds]

Originally Posted by Len_Beach

Mick; a huge thanks!

After finally sourcing a working copy of Rheingold; I think I've finally managed to clear this fault code.

It couldn't come soon enough as I now have a 480a DPF fault which I believe is due to the MAF fault preventing re-gens.

I'll try the old clear fault code method of it persists.

If anyone has a 3FC0 fault; follow Mick's directions above.

Thanks again Buddy.

You're most welcome, mate.
I'm glad it worked for you.
Cheers!

[Mik325tds]

Originally Posted by Hoooper

Glad to hear youre back up and running. Can you PM me where you found rheingold? Im thinking I want to get up to speed with that software since ediabas really doesnt do it for me.

Sign up at cartechnology.co.uk ($10 fee) and look for posts by Beemerboy88 or spider80. Their links usually work.