The idle on my car is all over the place, but never below about 1300. Last time I set minimum idle it helped, but now its out of control again. I know I have some bad injectors, and I'm changing them this weekend.

Question is...can I troubleshoot a MAF. I do know that when its disconnected, the car will not start. I've read of some guys disconnecting and the car keeps running. Not mine.

Thanks.

 

Some times you can tap it with something. If some thing is loose inside it it may jar it loose and cause it to act up.

 

Should the car run with the MAF unplugged?

 

Yes, and yes.

Yes, the engine should run with the MAF unplugged. However, if the engine is modified, the default fuel tables may not be suitable.

And, yes, you can troubleshoot the MAF with common instruments.

 

My motor has no serious mods. If i can get the idle down to 8 or 9 hundred, I'll try the check. I assume that's voltage you are reading in the pics. Do I just push my leads into the back of the MAF plug to get a reading? Sounds like it's bad, though since the car only runs with it connected.

Thanks

 

Backprobe the electrical connector to read voltage between the B and C terminals (C is positive). Make sure the MAF is connected and start the engine.



It actually sounds as if the MAF may be working and there is another problem, like a vacuum leak or fuel pressure/delivery issue. The voltage test should reveal that.