BMW E46 Fanatics Forum banner

41 - 53 of 53 Posts

·
Here to serve y’all
2004 330Ci 85k miles
Joined
·
11,617 Posts
Genuine BMW to VDO
Does it seem like the old MAF was over-reporting air mass?
I ask because I had a similar problem with negative LTFTs on a genuine BMW MAF that was less than 5 years old, and only solved it with a new VDO MAF.
 

·
Registered
Joined
·
31 Posts
Discussion Starter #42
Over reporting. Their was build up on the wire which i cleaned but I don't know how old it is so I just went brand new to save me the headache.
 

·
Registered
E30M3 Race F10 535 R1150Rt M Coupe
Joined
·
1,533 Posts
I have two cans of MAF cleaner here, that remain with 90% full. FWIW I've never had a satisfactory long term outcome with cleaning MAF's.

Cleaning (if it doesn't damage it) one and if there's a change for the better only proves a new one is needed.
 

·
Registered
Joined
·
31 Posts
Discussion Starter #46
I have two cans of MAF cleaner here, that remain with 90% full. FWIW I've never had a satisfactory long term outcome with cleaning MAF's.

Cleaning (if it doesn't damage it) one and if there's a change for the better only proves a new one is needed.
I agree. I didn't get the MAF code until probably 2 weeks ago which confirmed my diag. The LTFT was high because it just "learned" to dump fuel to compensate for the "unmetered air" (oil residue) on the hot wire. The interesting part was when I got the CAN torque reduction on my recently rebuilt transmission. I had no idea the MAF would tell the ECU to limit torque. I regained a good amount of power and it pulls very nice. I still need to do my front suspension overhaul and coolant system overhaul and she'll be perfect.
 

·
Here to serve y’all
2004 330Ci 85k miles
Joined
·
11,617 Posts
...I got the CAN torque reduction on my recently rebuilt transmission. I had no idea the MAF would tell the ECU to limit torque.
The EGS gets some important data from the DME, such as throttle position, load, RPMs. It’s not obvious, but engine issues affect the transmission in unintended ways.
 

·
Registered
2004 325i automagic
Joined
·
2,193 Posts
I agree. I didn't get the MAF code until probably 2 weeks ago which confirmed my diag. The LTFT was high because it just "learned" to dump fuel to compensate for the "unmetered air" (oil residue) on the hot wire. The interesting part was when I got the CAN torque reduction on my recently rebuilt transmission. I had no idea the MAF would tell the ECU to limit torque. I regained a good amount of power and it pulls very nice. I still need to do my front suspension overhaul and coolant system overhaul and she'll be perfect.
Normally the MAF should not get oiled up. By any chance, is there an (over) oiled K&N filter? Perhaps a broken airfilter box letting in unfiltered air?

Fwiw, when I had a soft failing fuel pump the DME (aka ECU) put the slushbox into limp home mode (4th gear only, could not rev above 3k or 4k rpm, and the "trifecta" lights came on), so drivibaility issues can affect transmission output in certain cases.
 
41 - 53 of 53 Posts
Top