The car started doing this 2 days ago and it's just gotten worse. It would first feel like it misfired and the SES would pop up for a few seconds and go away. Today it's gotten to the point where it stalls out in the middle of driving (mostly from a stop).

I scaned the car yesterday ant it gave me a - 48 MAF failure -

I'm thinking of replacing the MAF with some stock thing from Advanced Auto, should their be anything else I should look for?


The car will rev fine at idle, but as soon as its put into drive it'll stall or cutoff.

 

Pull the harness connector of the MAF, key-on, read the voltage between the pink wire and the black/white wire. Should read 12V. That means you have power to the sensor. If the wiring is OK, good chance its the sensor. If you have a multi-meter that will read frequency, I can tell you how to test the signal from the sensor.

Do not use some generic auto parts stuff (I doubt they even make them).... use a genuine GM part.

 

Look it up at Advanced auto and they do have one in stock, if it's a GM/ACdelco product I'm not sure.

I'll look into the voltage.

 

How do you test frequency?

 

One other thing to check before the frequency test is to see if you have 5 volts DC between the yellow and black/white wire with key on.

If that's ok you can check the frequency response with a multimeter that reads frequency available at Sears or Radio Shack.

Set the meter to Frequency(Hz) and check from the Yellow wire to ground. With the engine running, snap the throttle and be sure the meter reads over 7KHz. If it is lower, try cleaning it. If it is still not higher, replace it.

 

Didn't have a chance to look at the voltage as my multimeter is at work, but i did take off the sensor and clean it with electric part cleaner.

I was thinking that a possible cause of the problem might be the voltage the alt. is putting out. I have a underdrive pully on it and do notice that when sitting it does fall in the red part of the dash gauge. And most of the problem is when i try to start from a stop. I'll look more into this later.

Am I suppose to get 5v or 12v from the connector? Their are 2 different voltages to look for in this thread.

 

Both 5 volts and 12 volts. With KOEO, yellow to black/white is 5V +-1 and pink to black/white is 12 V.

When the engine is running check the yellow wire to ground for frequency response when you snap the throttle. Must be over 7KHz.