NHRATA01

Hi guys, hoping someone here can help me with a couple quick questions. My '89 started throwing an SES this weekend, scanned it and got codes 33 (MAF or MAP voltage high at idle) and code 45 (rich exhaust - O2 sensor voltatge high). Car idles rough and surges when coasting (A4 trans). Is this pretty much a clear indicator that the MAF has gone bad, which is what I suspected? Or could something else cause this, like maybe an exhaust leak, which I have had for some time now. I wouldn't think that would throw the MAF off, but who knows. Also, does a MAF setup have a MAP sensor, or is a MAP sensor only used for speed density systems, since the code could be for either sensor? Just wondering if I have to troubleshoot 2 sensors. Thanks alot!

Edit: I should mention, I replaced the O2 sensor a year ago when I replaced the cat...so hoping that hasn't crapped out yet.

Camar_Hunter_c

I think with the V6's they had one ot the other, a MAP or MAF. So if its a MAF sys, then the MAF has crapped out. If I remember correctly, the new LS1 systems have both.

You can have the MAF tested with an Volt meter to see if anything it off there. I don't know how to check the MAF though, I havethe better of the 2 systems, S/D. I even have a 89 350 MAF harn harness that I am repinning to convert to S/D.
As far as the O2, I have a A/F guage on mine so that I can keep tabs in it.
And if I suspect something I hookup my laptop and have a look around at the data while driving just to get a good picture.

Dale

iTrader: (12)

You either have a MAP, or MAF, not both. I belive 89 uses MAF.

Rest, I'm not sure off. I think it is possible that a bad MAF will cause it to run rich.

BTW, noticed this is your first post, I welcome you.

Camar_Hunter_c

Forgot, yes a bad maf will run either way, rich or lean.

The Rich exhasut code, just tells you that your getting to much fuel(insert Collin with Captain Obcvious),
But it DOES tellyou that YOUR getting fuel(a good thing). So your left with trying to troubleshoot air measurement systems. Hense MAF/MAP, MAYBE a TPS. Yiours threw a MAF, so Bingo.

NHRATA01

Thanks guys, I figured it was one or the other depending on MAF or SD. And thanks for the welcome I've actually had my '89 for almost 7 years now, and at 109k miles honestly has been trouble free save a clogged cat. Body is still in perfect shape and rust free, not too shabby after 7 NY winters. Well looks like I'll be ordering a new MAF then. Thanks again for the help!

Nixon1

I was told that the older MAF cars had an MAP also but that it wasn't nearly as important as it was when MAF was eliminated and they switched over to SD...

NHRATA01

Well, picked up my new MAF today, and 285 bucks and 20 min later had the car running right again. Damn, couldn't believe the price for a MAF! I bought a nice descreened, ported LS6 MAF for my T/A for almost half the price! Anyways, thanks for the help fellas. Take care.