MAF Failure Symptoms?

[MrHeavyFoot]

Anyone had a MAF fail on them? I've been experiencing some problems with poor acceleration under WOT at higher RPM's (>4000 or so). The boost stays up the whole time, but it feels like something is pulling back on the car. It can be pretty noticeable at times and produces quite a jerky motion. Also, one guy mentioned that he thought he saw a little smoke coming from the exhaust when I was accelerating, and thought maybe it was running rich, which I guess could be a sign of a bad MAF.

Any ideas?

[QuA]

Re: MAF Failure Symptoms?

I tried unplugging my MAF today and I didnt even get boost. Every gear when I changed was very rough. Dunno why.

QuA

[MrHeavyFoot]

Re: MAF Failure Symptoms?

I tried unplugging my MAF today and I didnt even get boost. Every gear when I changed was very rough. Dunno why.

QuA

That's odd. The posts I was reading on the vortex said to unplug the MAF to see if the symptoms went away. They said you could run with it disconnected for a while with no ill effects other than maybe running a little rich.

[Bighead]

Re: MAF Failure Symptoms?

Yeah, you've got typical MAF failure symptoms... that dip in the powerband around 4000 is the clincher. Go to Shoppers Drug Mart and buy some high purity Isopropyl Alcohol, soak your MAF in it, let it dry overnight, and put it back in. That may help a bit. Also, try driving around with it unplugged - you'll get a CEL and ASR off but the car will likely run smoother.

If none of that works, you need a new MAF. VW just recalled these, so you can try taking advantage of that. If not, you're looking at $80-$380, depending on your engine code (AWD is $80 and AWW/AWP is $380).

[MrHeavyFoot]

Re: MAF Failure Symptoms?

Yeah, you've got typical MAF failure symptoms... that dip in the powerband around 4000 is the clincher. Go to Shoppers Drug Mart and buy some high purity Isopropyl Alcohol, soak your MAF in it, let it dry overnight, and put it back in. That may help a bit. Also, try driving around with it unplugged - you'll get a CEL and ASR off but the car will likely run smoother.

If none of that works, you need a new MAF. VW just recalled these, so you can try taking advantage of that. If not, you're looking at $80-$380, depending on your engine code (AWD is $80 and AWW/AWP is $380).

Thanx Conrad. They extended the warranty on the MAF to 7 years, so it should be covered, unless they complain about the chip. From what I've heard, Norden has replaced these under warranty on chipped cars before, so hopefully all will be cool.

[Khyron]

Re: MAF Failure Symptoms?

They won't give a **** about a chip but they will raise an eyebrow if you have an intake (we all know mafs are crap and die anyway but it's reasonable to assume an oily filter can increase the frequency)

Your fuel economy should be crap too if you have a dead/dying maf.

Khyron

[MrHeavyFoot]

Re: MAF Failure Symptoms?

They won't give a **** about a chip but they will raise an eyebrow if you have an intake (we all know mafs are crap and die anyway but it's reasonable to assume an oily filter can increase the frequency)

Your fuel economy should be crap too if you have a dead/dying maf.

Khyron

This is the exact reason I have never put a K&N filter in the car. Intake is 100% stock.

Fuel economy hasn't been that bad, except for my last tank. I was thinking it had something to do with the 23 autocross runs I had on the weekend, but the drive to Red Deer and back should have balanced that out. Fuel light came on at about 420 km, whereas I can usually get to 440 with mainly city driving. The trip to Red Deer should have boosted that to around 500-550 km.

Off to the dealer I guess.

[MrHeavyFoot]

Re: MAF Failure Symptoms?

Well, took it into Norden tonight and they said the MAF was fine and they couldn't find anything else that would be causing the problem. They agreed it was pretty flat above 4000 RPM though. Naturally, they blame the chip. Went home and did the MAF cleaning thing just to prove it to myself. Just got back from the test drive and it seems a little bit improved, but there was still some hesitation on a couple of pulls. Accelleration seemed better over 4000 RPM, but my butt dyno isn't calibrated too well, so that could have all been placebo effect. Also, the problem always seems worse when there is a lot of heat in the engine and maybe the cooler night air was helping things out a bit. I guess I'll try disconnecting the MAF tomorrow and we'll see what happens.

Farg.....