thermo

anyone know how the MAF is grounded?

kday

All or nearly all of the sensor grounds end up there.

Check out the connector itself too. Did you try disconnecting the MAF when it was running badly like I suggested?

thermo

you're saying that I should disconnect the MAF when it's running poorly. Should I take it that if I disconnect it and things don't change (i.e. still runs poorly with no change) then the MAF might be at fault? Kinda like when diagnosing a POS problem and pulling the power to each injector and seeing if it makes things worse or not?

kday

If it was not running at all, then if you pull the MAF and it starts running, that points to the MAF acting up. The ECU will limp along with no MAF, although from what I recall of the sound of Tom's car with no intake or MAF hooked up, it won't sound happy (but maybe that was the no-intake part).

I would think that if you disconnect a good MAF, the engine should run noticably rougher, but that's pure speculation on my part. No BTDT.

Check the harness with an ohmmeter. Flex it while doing so. Maybe you have a loose wire.

MAF pinout:
1 - ground at valve cover
2 - ECU pin 26
3 - ECU pin 7
4 - ECU pin 25
5 - +12 from fuel pump relay, also goes to ECU pin 37 and high side of fuel injectors
6 - no connect

S4-Fireblade

At least it didn't work for me; By what I can remember, when I disconnected the MAF's plug the idle would get lower and the car was almost impossible to drive. And the MAF was still not working fine- solved with my old/used MAF.

S4-Fireblade

Wouldn't that cause false readings to the ECU? Just a guess...