TALMADGE

I got a code 33 yesterday, replaced the burnoff relays and everything was fine until today. Code 33 agian, thought to replace the Map sensor. I can't seem to find it. Like me it is problably staring me in the face. Any help would be alots of help. :yesnod:

JAKE

You don't have one. They're on Speed Density systems.

Be sure to clear the stored error code by disconnecting the power to the ECM for about 30 seconds. Then restart the engine and see if the error code recurs.

Jake


[Modified by JAKE, 3:25 PM 4/17/2004]

vader86

Code 33 is a MAF sensor/relay problem. There is no MAP on 85-89.

If you have replaced both relays and reset the ECM by unplugging the battery, the problem is likely the MAF sensor itself.

86PACER

:iagree: With both of the above posts. :thumbs:

chucks88

My car was running very rough when when my MAF sensor was on it's way out. Do you have any friendly fello C4 members in your area that will let you swap MAF sensors to see if you get the same codes? Those suckers aren't cheap :cuss

Sam Lam

If you have a friend with a scanner, you can detect a MAF going South. Another option is to take it to a repair facillty and have them perform the scan function for you. It may cost you a few bucks, but it is cheap considering the MAF sensor will cost you about $250.

JAKE

I did the same thing when I suspected my MAF was bad; I borrowed one off my buddy's 85 Vette and the engine ran normally again.

I bought a replacement for my 86 from a wrecking yard a few years ago for $50

Some of the 'F' bodies come with the same MAF so finding one shouldn't be too hard.

Jake

TALMADGE

Thanks for all the advice, Funny how advance auto parts lists a Map sensor for a 88 when it doesn't have one. I have a friend that owns his own shop, I will see if he can narrow it down to the Maf sensor. Thanks for all of your help and keep on :steering:

RedCorvette1988

I had the same problem on my 1988 the code said it was the Maf. I tryed two new mafs and didnt fix it. I then tryed another maf that I knew was good Still no luck. Finally I replace the computer and fixed the problem. It runs great now and I am using the old maf. The computer was cheaper than the maf. ------------ Hope this helps

joedirt001

i know this is an old post ,but , i have replaced both relays ,the maf with a rebuilt oriellys $56.00 one and the ecm. still with hesitation? any ideas ???

GREGGPENN

The MAF plug itself. Or, the wiring between the MAF and the ECM. Or, where it plugs into the ECM. Or, the ECM itself.

Check for wiring diagram(s). Seems like one pin should carry either 5 or 12V. And, other should vary with rpm.

MAM makes a test kit for to help with the plug issue....http://www.mamotorworks.com/corvette?frame=3.878

Oh yeah...How about low voltage from the alternator/battery?

rodj

Why do you think you have a MAF problem;do you have any engine codes showing?

http://www.chevythunder.com/maf_code_33.htm
http://www.chevythunder.com/maf_code_34.htm

Corvette40

We had a guy bring his 87 in because it was running rough and he wanted us to take a look. He said a shop in Riverside had the car for two weeks and couldn't find the problem. It sounded like a MAF issue so that's where we started, plus it one of the easiest things to eliminate as a problem. We unplugged the MAF and the idle evened out so we began checking continuity between the power relay and sensor. There was no continuity between two of the wires. We found that the wire loom had made contact with the belt and cut the two wires. It took us 30 minutes max.
Take your time, follow the troubleshooting procedures and advice above and you'll find your problem.

65Z01

Some years ago the MAF in my '88 was bad, I swapped in the MAF from my '86 IROC-Z and it ran great, even had same values as shown by my scan tool.

joedirt001

thanks everyone ,no codes showing. put an aftermarket MAF in for $56.00 in and that is the only thing i can think it could be. one day this 88 will run good and the next the miss reappears? am about fed up and ready to sell again... will take a pill and try again later THANKS !!!

cgantner5150

I chased a MAF issue for a bit. It ended up being the TPS. The ECM does a check of airflow vs throttle position. Use a DVM to check for smooth operation from .54v at idle to 4.5v to 5v at WOT.

James Clancy

there isn't one on an 87 or 88 what code 33 comes up it's the MAF sensor or relays

James Clancy

there isn't one on an 87 or 88 what code 33 comes up it's the MAF sensor or relays

James Clancy

there isn't one on an 87 or 88 what code 33 comes up it's the MAF sens9or or relays

WVZR-1

James Clancy

You've just posted to a thread that's several years old!! I'm sure you intended well but I'd think all posters prior to you have sorted their issues and moved on.

If you meant to ask a question just ask.

3 times the same what's up?