Code 31 (MAF) but weird symptoms

[shipkiller]

it's a 7mgte with 550cc and lex maf.
Everything is good until the car get warmed up to operating temps, then for like a minute or two, when I hold a constant speed, the car will let off the throttle and snap on it, kind of like fuel cut (but it isn't) and MUCH MUCH MUCH MUCH less aggressive and obvious, it does it on the cruise control too, speed doesn't matter much, but when I accelerate or reduce speed, it's fine. It is really at constant speed.

then after the said minute or two, it will be all fine!. also the car will start to stall at idle and neutral after that problem happen and the CEL will light up randomly at random speed/rpm/condition.
The only code it throw is 31 and 43 (the latest one (43) is alway present, I alway had this code so it's not related). 31 is the MAF, but the car has some moment of good drivability and no problem at WOT. Is it the MAF or something else (miscalibrated TPS ?)

thanks!

 

[mk3_7m]

Bad Maf sensor "edit afm" Replace it. Ideally you wouldn't want any codes on your car, particually those ones.

43 is starter signal. Might have to check the wiring.

 

[Nick M]

Your car doesn't have a "MAF". This is why it goes before the blower and not after. 31 means nothing about whether the air flow meter works or not directly, but it states that the signal the ECU from the airflow meter isn't being input. Now, the airflow meter might be dying. Or you have a bad connection. You can test it with a fluke on Hz.

How do you know it isn't fuel cut? Fuel cut has multiple forms. Overspeed, deceleration, abnormal turbocharger pressure....deceleration does what you are describing when the TPS has a circuit problem. Are you sure it is 43 and not 41?

 

[shipkiller]

well, for instance, Why would I hit fuel cut @ 60kmh without any acceleration and without the CEL lighing up, and this not as hard as Fuel cut. Plus how could I hit fuel cut when in vacuum?
yes I am 100% sure for 43, I always had 43 for some odd reason but I never had problem with it. I'll test the afm with a resistance meter today (according to the tsrm)

 

[shipkiller]

Tested the maf. it was around 12C outside and got 2900ohm. swapped the electronic from my old working maf into the lex housing, pulled the efi fuse and then went for a drive (after a oil change), only stalled once when it was cold (ecu still learning perhaps) and went fine for the rest of the trip.

hope I fixed it