I tried searching, can't find anything pertaining to my exact problem.. and don't know if this is the place to ask.. but I will.

89 5.0 TPI, GTA.. I will be driving down the road, minding my own business.. pull up to stop sign. And boom.. Service light will come on, I'll almost stall, car bogs when you try to give it any gas... only fix is to wait until the Light goes out.. 10-15secs.. sometime 1min.. happens more than I would like it to.. Only thing I can say is that the guy I bought it from said the screens are out.. and on the filter side it is.. Any reccomendations? I know the screens removal is a bad thing..

Thanks
Thirim

89 GTA

 

Check all of your wiring in the engine bay, look for anything that looks like it has been burned. Also, disconnect the MAF plug and check the pins inside the connector, make sure that they are straight.

Pay special attention to the wires that are near the exhaust manifold or headers.

Also, find out if the ECM has thrown an error code. Do you know how to do this?

 

I had similar problems. It turned out to me my MAF sensor. Also I ended up having to replace my ECU before it was over. Fortunatley the ECU wasn't that expensive. The MAF on the other hand is kinda pricey. For what it is anyway.

 

I had that same problem and a garage told me it was the MAF. I changed it and the car still kept stalling. So I put back on the old one and tryed changing the MAF burn off relay. Problem solved! So try changing that relay before you change the much more expensive MAF sensor.

 

Ok.. I did get a code out of the ecm.. but forget what it is.. (will check that again in the morning) but the code was a MAF code.. I managed to search and found a pic of the MAF relay location.. will check that. And will look for bad wiring.. There is nothing worse than pulling up to the lights with your flowmaster exhaust and 5L of muscle.. only having to limp away...
will let you know what I find..
thanks..

 

OK.. pulled my codes.. I'm getting Code 34. I unpluged the MAF Burnoff relay. found lots of greese.. I took the electro contact cleaner to the contacts. there was a black wire which had about 1/4" insulation bared at connector. Is this ground? And can you buy those ends so that I could replace that wire end? Does the screen(s) being off upset anything? Anyone have a pic of there screens? I have a screen that guy handed me when i bought the car but it doesn't seem to fit.

Thanks for the help

 

Code 34= Low MAF voltage. The ECM is seeing voltage from the MAF that it thinks is lower than it should be, based on other sensors and engine parameters. This could be from a bad burnoff relay or just plain bad MAF. This can also be from false air entering the intake tract AFTER the MAF. Before replacing the MAF or ECM do some troubleshooting.
With the engine warmed up and at an idle (ck eng lt off) gently rap on the MAF housing and see if it turns on the ck eng lt and starts running poorly. If it does the MAF is probably bad, but check the connector going to the MAF to be sure it is hooked up securely and none of the female pins in the connector are distorted.

Also, the grease in the relay connector is supposed to be there, it is there to seal out moisture and crap.
If you find that you need new connectors for the relays or MAF, you can find them at Pepboys ($20 for MAF and $14 for relay connectors)

Removing the MAF screens will not harm the MAF unless you damage the heated wire in it while removing the screens.

 

I got code 34 and ran around with my SES light on the last few months of summer last year. I took the screens out this spring getting it ready to hit the street oncew the snow was gone. Once I reinstalled the MAF and fired up the Formula and the SES light was out. Hopefully it will stay out, so far so good . I was told that for a new GM MAF it will cost $600 Canadian up here!!! Not exactly a cheap part!

 

I am in canada as well.. A MAF is like $630-$650, but you can get an after market for like $295 ish. My light is out most of the time.. But when you are in traffic, and it comes on.. even for a second. its enough to want to push it off a cliff.


I will try the above mentioned troubleshooting and will inform you what I find.. $20 for relays, I already have them on order.

 

i have the same prob now, i replaced everything related to the maf, and the ****in light is still on, i even unplugged the neg bat term for about 20 min, im at a loss of words.

 

Somewhere I have a whole troubleshooting proceedure for MAF's, I got it from a company that does ECM overhauls. I'll see if I can find it and post it here.

 

MAF power and burnoff relays are cheap. Since they are also the same as the fan and horn relays (among others), it's nice to have some spares around anyway.

But, I've found that most of the time the problem you describe has been caused by the MAF itself. If you need a new MAF, buy a Wells SU 145. It's the cheapest one you'll find, it's the ONLY one with a lifetime warranty, and instead of the unreliable thin wire design, it uses a thick film style like the LT1 MAFs. It also eliminates the burnoff circuit, so you don't need to worry about the burnoff relay tanking anymore.

Do a search for that MAF. When you do you'll find a phone number & address for a place in buffalo NY that sells them. That's who I ordered mine from.

 

how much?

 

The MAF? it's like $165. Do the search and you'll get all the info you need.