94 thunderbird MAF sensor ?

When tapping lightly on the maf sensor with a screwdriver the idle smoothes out stumbles and cuts off. The reading on scanner for the maf sensor goes from 2.02 to 16.36 in the two frames which I was tapping on it and it cut off. I've tried replacing it with a cheaper a1 remaned a1 cardone unit, which I should know better anyway, having sold the p.o.s products by that company for a few years, but I never said I was smart. So my question is, does this mean that my oem unit is bad being that it cut off and possibly the reman was a defect out of the box which I know could be possible? I checked the fuel pressure and it's fine,it doesn't loose pressure after sitting for about an hour with the car off, so I believe none of the injectors are stuck open. All the plugs are very black and sooty. At first it had a code 0174 but I've noticed once u mention that everyone ignores u. I've looked thru post after post on every 0174 issue and none compare to my problem. And I haven't located a vacuum leak yet. Any intelligent suggestions would be appreciated. Chrisndeepdodo

Reply to
chrisnrali
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Back in the mid 80s on Buicks with Delco MAF sensors, the test was to honk the horn, if the engine stumbled or died, the MAF was bad.

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It's a volumetric efficiency calculator, you can use it to determine whether your MAF is reporting close. Do WOT while recording your MAF PID, plug in the numbers and see where you're at. (no VE calculator is 100% exact, but this one is close) Also, what is the BARO reading from your scan tool, does it jive with your altitude? Since BARO is extrapolated from MAF on Fords, if the MAF is skewed, so might the BARO PID.

If you can graph data PIDs, graphing fuel trims is quite useful, if one bank goes negative and the other bank goes positive, I'd be looking at a restricted exhaust.

Reply to
aarcuda69062

I got it running semi normal (for it anyway). MAF sensor was bad and the vacuum hose that runs from the back left to the back right of the intake then to the pcv in the right valve cover was leaking in two spots, one at the rubber Tee on the back right and the rubber hose that connects the plastic hose to the back left intake had collapsed and split. The lt ftrm2 is still a bit off from normal. Could it possibly need a new o2 sensor? All the rich running playing around I did diagnosing it might have fouled it? Thanks for the help so far. Chrisdoingbetter

Reply to
chrisnrali

Were you able to clean the MAF sensor or did you have to replace it?

Reply to
F.H.

Rotten PCV hoses is so common on 4.6s, I'm surprised it wasn't suggested very early on.

Before you throw any O2 sensors at it, the new MAF needs to figure out what altitude you're at (it doesn't measure altitude directly), make some occasional wide open throttle runs over the weekend and then check your fuel trims and BARO PID against spec.

Reply to
aarcuda69062

It Was. See from 8-07-2007 above.

Lugnut

Reply to
lugnut

Indeed you did. :-)

Reply to
aarcuda69062

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