I have a 1991 RS Camaro 3.1L V6.. The car was originally automatic, and has been converted to 5 speed. When the car warms up, the idle becomes a bit erratic. it begins hunting from 400-900rpm, and codes 44 and 45 are set. Ive tracked down any possible vacuum leaks, none found. All sensors according to the scan tool are operating fine. Ive recently heard about the M/T cars having a decel valve. Im curious about any information anyone can help me with. Ive exhausted almost all resources trying to fix this issue. Thanks

 

Strange to have both code 44 & 45 set. As one is O2 lean and the other is O2 rich.

Your best bet is to get the proper MEMCAL (PROM) for that engine and transmission. Which is BAWX. This is due to how the ECM controls the idle fueling.

Then once installed reset the ECM by removing the inline fuse for a couple of minutes. Then start the engine and let it warm up without touching the throttle or steering wheel. Turn it off for about 20 seconds and done.

RBob.

 

Ok, Im keeping my eyes peeled for the ECM, also I was curious if the car required the decel valve as well. Im at wits end on this one, Ive been fighting the idle issue for quite some time, found no issues with injectors, vacuum leaks, etc. It only happens after the car has reached operating temp, and it can also be induced by pumping the brakes which suggested to me a possible vacuum leak, yet havent found one

 

Im willing to bet it has to do with the memcal also.

It never tossed out any other codes then what you stated above?

 

No other codes.. yet "knock on wood". Ive been looking all over the forums about the BAWX Prom for the car, Ive even though about the Hypertech prom for a 3.1 5 speed, but I heard it isnt worth the money.

 

I don't think the MEMCAL is going to solve your problem. Also, good luck finding a BAWX. It's hard enough finding a V6/5-speed MEMCAL from 90-92 much less that one.

When mine was running right (that blasted harness!), it ran fine. I was running an AUJW (1991 automatic) MEMCAL on a 5-speed, no decel valve, no AIR pump, no nothing (didn't even run EGR with that harness as I didn't have the right valve). It ran fine until it started having the ignition cutting-out issue, which is why the harness was yanked for good and cut up. Don't say it wasn't the harness as my other, factory 1987 302 harness didn't have this issue with the same parts (ignition and fuel), and yes, I did replace the ignition module (and even the whole distributor) and tried another ECM.

Check the output of the MAP sensor (voltage between green wire and black). I don't know how you checked the injectors and for vacuum leaks, but if your idle is that low, you've got an issue. Oh, and check to make sure the EGR valve isn't sticking open.

Reset the ECM and do an idle relearn first. Then you will know for sure what code is current.

 

Dont buy a hyper-chip. Waste of $$ in my mind. You could burn your own chips for close to that cost.

Reset the ecm and see if its still saying those same codes. Makes me wounder why its saying o2 rich and lean at the same time. Thats what makes me think its either a ecm or memcal issue.

 

pm sent , I have some 3.1 memcals I could reprogram one for you and I have 730 ecm's if that helps.

 

Sounds like you have a intake gasket leak. Take a spray bottle with water a spray around the intake if the idle changes you need to replace it. hope it helps.

 

Thanks, already searched for any source of vacuum leak, including intake.. None found. Im still searching for the BAWX prom for the car, it's not so much an option to remove my ecm and send it out at the moment being the car is my daily driver.

 

I had a similar issue with my son's car. It is an automatic, but it would idle fine at startup, then shortly after, the idle was very erratic. Turned out to be a plugged cat an a partially plugged muffler. replaced both and it runs fine. Not sure if its the same issue. We figured it out by removing the O2 sensor so it could breath through the open hole.

 

It's definitely not that. My car does not have a cat and the muffler is fine.

 

Idling issue resolved.. No more code 44 and 45... Installed the correct PROM, broadcast BAWX.. Car runs 10x better

 

awsome