Binding Air Flow Meter

[Oddmanout84]

This fix is a no-brainer.

 

So I had this problem recently, and since it technically does deal with your fuel delivery system, I'll post it here.

 

This is for any fuel injected Z that has the old flap style Air Flow Meter, not a MAF...

 

The last time my Z ran, about a year ago, I was puzzled as to why the engine would not rev above 2500. Everything else in my system seemed to check out right, and I even removed the nice little nest some mice had constructed in my intake. I could stomp on the pedal and still the engine would falter at 2500, almost as if it had a rev limiter on it. I didn't have time to fix it then, as i was only visiting family and had to go back to the west coast for work.

 

This year I started taking the car apart, and when I came to the air flow meter I found that the flap was halfway open. sticking my fingers in to push it, it seemed like the flap would overcome whatever obstruction and work normally. But when pushed back the opposing direction, it again met resistance at a certain point.

 

Not to debunk the advice that Wizardblack provided me with, but I had already tried spraying PB blaster to try and break up the gunk on the hinge, and even worked it back and forth for about a half hour with no progress! The back plate screws were all very tight and painted in to the surface, so warily i used my dremel to cut slots in them so I could use a flathead screwdriver. This is what I found.

 

 

a closer look

 

See that little bright spot in the center? that's where my flap was catching. The upper portion of the flap as you can see runs very close to the casing of the unit. Somehow the metal had deformed and was ever so slightly bulging in and catching the flap. The method I used to find the exact area was to shine a small surefire flashlight behind the flap as I moved it. So I got out my favorite toy: The dremel. For this I used one of the standard cylinder shaped sanding tubes and a steel wire rotary brush.

 

I did not have an extra hand for taking in progress pictures of my sanding (I don't even have a vice) but the method I used was simple. I set the dremel to 15000rpm and made even flowing motions to sand out the problem area in the direction of the flap's travel. Don't go too slow or linger in one area too long, or you'll end up with an uneven surface.

 

This is the finished product

 

I then used the wire brush tool to smooth things out a bit more.

 

 

Then I got carried away and commenced making everything shinier.

 

End product: one worn sanding drum and a scraggly looking wire brush. I highly suggest wearing goggles during this operation, as little wire bits will be flying at high velocity in all directions. For that reason you also shouldn't operate the little dremel brushes above 10000rpm. This is why the next step is picking the wire bits out of your arm...

 

Use some air to blow out all the metal particles and you're done! Test the flap to see that it moves freely, and repeat sanding if necessary. Try to limit the amount you shave off to just the right amount of clearance for the flap.

 

The process should take about 15 minutes with a dremel, a bit longer if you were feeling froggy and did it by hand.

 

Now wouldn't you feel silly if you went out and bought a refurbished unit?

[WizardBlack]

Nice job! Certainly a good post and nice pictures to match! Mine was stuck when I bought it, too.

 

An alternative for someone without a dremel (or afraid their hands aren't steady enough) is to grab some 3M Wet-or-Dry 600 grit sandpaper and get it wet a bit and run back and forth across the slope (along the direction of the slope) while providing even pressure. It should also knock down imperfections and get it working well again.

 

Let us know how it's running!