MAF 2783 fault e46 N42B20

[alijanjan 3]

Hi all

I'm having problem with my e46 N42B20 again where I get a maf sensor fault which in turn puts the transmission in limp mode

I scanned it with inpa and it comes up with 2783 CDKLM hot film mass sensor and says signal over threshold old shorted to positive, 

I have a brand new oem maf sensor,  I've already checked for Vacuum leaks,  ccv is good. I've taken inlet manifold out and checked for common leaks. Couldn't see any, dipstick oring also ok

I have pulled the two signal wires out of maf and ecu and ran a pair of cables directly and still the same fault 

5v and 12v wires at the sensor read ok

I'm at a loss and was hoping someone can help here. If I was still in Auckland I would have definitely gone to Glenn by now, 

Worth mentioning that the vvt faults are also present, learn limit necessary,  Eccentric sensor but these have been like this for couple of years 

I have also somehow got engine oil wicked into the ecu connectors which I have cleaned with contact cleaner ( I had an oil leak from filter housing that had the wiring harness soaked in oil, but fixed now)

Secondary air pump was also noisy and when I went to check it, the pressure hose snapped. I have temporarily fixed it until new hose comes in

Sorry about the long post but having no luck fixing the problem

This same  maf sensor code came up 1-2 years ago when I checked everything but didn't find anything back then but the fault went away for long time, 30-40k driven since then and now it's back

Any help with be greatly appreciated 

Thanks

Edited October 2, 2020 by alijanjan
More details in the topic

[Tom 11]

Hey Alan,

Any luck finding the cause of your MAF sensor issues on your E46 N42B20 mate?

I’m interested because I’m getting the same type of issues on my E46 N42B18 (2001 316ti Compact). It was my grandfather’s car, bought new in 2001. When I got it back, it was not in great shape. I changed all the fluids, spark plugs, SP wires, filters and it was running again. But I was getting DTC codes on the MAF sensor, secondary air intake, and VVT sensor. On the road, the car was driving ok, but quite often, the RPMs would drop while accelerating, especially when asking for torque in the low / mid range rpm. Eventually one summer day, I started the car (after having let it sit for a couple months ) it ran as usual for a few hundred meters and then no response in the accelerator pedal, just an erratic idle like a slow heartbeat. I could only get a tiny bit of engine rpm, maybe 1100 rpm that’s it. I got around it by unplugging the MAF sensor.

I cleaned the engine the top end near the VVT connector where there was a bunch of oil, and put a new MAF sensor in. Problems were gone and the car was running perfect. I drove it about 30-40k and now I’m getting issues again. What it does is different now. When I start the engine, it goes in heating up phase and after a minute or two, it stalls unless I play with the gas pedal. It won’t hold its idle.

This issue developed overnight when we recently had very low temperatures in Paris. I had just driven it a 1000 miles back and fourth to the west coast of France with no issues whatsoever.

I’m thinking about changing the MAF again but is it normal that they go bad that quickly, or is it related to another air intake related issue? Vacuum leaks?

BTW, I’m not getting those VVT codes anymore after the big cleanup, so that’s a relief. But what I did start getting for the past 4-5 months is a bad smell coming from the engine bay and eventually in the car if I blow the vents without the A/C on. I’m suspecting the FAP / exhaust filter located to the left of the engine, next to cylinders 1 and 2.

Any leads or help on what do next would be very appreciated.

Sorry for the long post.

I just made an intro of myself and the car in the new members sections but I’ll post another pic of the E46 here.

Cheers and good shifting

Tom