Hey ya'll. I've been away for a while but need your expertise once again. My sister has a 2000 SS that had the MAF replaced about 8 months ago. Now all of a sudden it randomly dies when she accelerates. Somedays its fine, some its not. It may even happen in the middle of a trip. Autozone is saying it's a MAF sensor code. One shop is saying it may be a cracked head or head gasket.

My questions to you are
1) Does that shop's preliminary diagnosis make any sense? I've never had experience with what symptoms a cracked head or head gasket would do.

2) any common MAF related things to look for?

Thank again!

 

Unplug the MAF and see if the problem goes away. If it does, then the MAF is most likely bad and would need to be replaced again.

 

A dirty or failed MAF can cause a lot of screwy and intermitent things. In the short term, you can disconnect the MAF and see if the issue goes away (as the computer then compensates for no MAF reading). This is NOT a permenent solution, just a testing point.
Next, I would check the warranty on the MAF part used. If it's a 1 year warranty, go directly to the exchange line and swap it (takes 5 minutes to remove, but you need a security torx bit to remove it).
If it's not under warranty anymore, get the MAF cleaner from the parts store and follow the directions on the can (it costs less then $10 for a can, a new MAF as I'm sure you are aware is pricy).

As for a failed head gasket or cracked head, these would not throw a MAF code and you'd have more consistent issues (such as, but not limited to):
- Mis fires
- Coolant lose
- Poor performance

You have a CEL code that does match your symptoms. Diagnos the MAF and go from there.

 

Where did you get said MAF from 8months ago? If it is a generic MAF off Ebay then it was amazing she got 8months out of it.

 

check the air filter. seeing how she's a woman she probably never has replaced it. i've seen a clogged air filter cause that issue.

 

That is a really sexist comment. I would advise against statements like that.

Second, it's worth checking the air filter, but typically when these cars throw a MAF code, there is something up with the MAF causing it. But it takes 5 minutes to check and air filter, so worth not ignoring it.

 

My opinion about MAF problems is posted here:

https://montecarloforum.com/forum/en...18/#post541287

I don't think a dirty air filter is causing the problem. The PCM should adjust fuel delivery to coincide with the amount of air the engine is receiving. Of course, if the MAF is not working properly...

 

Air filter was something I thought of, but did not relay it as it was changed with the MAF. What about the clogged Cats I've been reading about? Would behave similarly, no? Or would that not throw a MAF code?

 

If the catalytic converter is having issues you might get the check engine light with a p0420 error. Mine was clogged but that resulted in reduced power and would also make a whistling sound under acceleration from the back pressure. But, a simple check like holding your hand close to the tail pipe while someone revs the engine would tell you if it is seriously clogged. You should feel substantially more exhaust as the engine revs.

 

You actually have a MAF CEL code. It's not a clogged cat.

I agree with 03SSLE about the air filter should not cause the problem (it was a quick check, plus if it was dirty, it might be promoting dirt getting on the MAF resulting in problems there, but in honesty, it is a long shot).

More then likely, the MAF is bad.