MAF Troubles

I'm starting to think my car is cursed lol ok I'll see if I can explain with going on to long. About a year ago I got the old p0101 code and just assumed it was the MAF so I changed but still couldn't get rid of the code. Fast forward to a month ago I had a feeling about the MAF that maybe it was the wrong one , sure enough it was for a gas engine ( I know I should have checked before I installed it) so I swapped my old one in and the car ran better for a about two weeks then it was all down hill from there. I'm guessing the MAF gave up the ghost and put the car in limp mode so I unplugged it and the car runs fine not as much power but runs at least. So I bought a new one (the right one this time) put it in and the car runs like crap with no bottom end power, I checked to flow rate and it was at 220mg/St so I thought maybe it was screwed and exchanged it and the same thing. With the MAF unplugged it's at 550 but never changes , with the one from the gas engine it idles around 530 and goes up as it should but I'm guessing not as high as it should. Does anyone have any idea why the wrong MAF works and the right one doesn't?

Where are these new MAFs coming from, what brand?

I'd look to clean the harness connector and dab with a bit of dialectic grease.

It is possible that you have a bad wire in that harness.

Did you check all boost hose connections? I had this P0101 code also, and it turned out to be the small hose on the bottom of the inter cooler; the hose became uncoupled due to worn barbs/nubs.

I can't remember what brand the new MAF is but it's not a Bosch but it's not a $10 out of China one either. Im going to have to test the connections I guess I just figured since the "gasser one" worked ok the connections were ok but I'm going to check them anyways. I do have a boost leak on the lower hose at the intercooler nothing crazy but I do need to fix it. My original MAF (which puts the car in limp mode) is a Bosch same with the Gasser one.

MAF may be fine, you can't just replace part named in code.
Try this- from the Ross Tech wiki

Beerbaron666 said:

I can't remember what brand the new MAF is but it's not a Bosch but it's not a $10 out of China one either. Im going to have to test the connections I guess I just figured since the "gasser one" worked ok the connections were ok but I'm going to check them anyways. I do have a boost leak on the lower hose at the intercooler nothing crazy but I do need to fix it. My original MAF (which puts the car in limp mode) is a Bosch same with the Gasser one.

Click to expand...

You're changing the things that are being connected. While one can assume they ought connect up the same it is not a certainty. This is electrical stuff. AND, if it's not a Bosch replacement then there's less certainty.

As critical as MAFs are I cannot fathom how people can think that it's OK to scrimp on them. I replaced one on the wife's car at over 150k miles (and 16 years). A $100 part. One on my car has about 166k miles and I'm thinking that it's just getting a little tired- again, $100 and no more head-scratching (for perhaps another 150k+ miles).

Another possibility: an EGR valve that's sticking open a bit can cause "MAF signal too high" code.

Easy to check: pull the EGR valve, plug it back in to the electrical connector while it's lying on top of the valve cover, and then run the "exercise the MAF" test using VCDS.

BTDT, got the MAF we didn't need to buy to prove it.