I'm Having problems with my 91 TBI Camaro. Car stalls on me every once in awhile. Problem is it starts acting up while I'm driving our stalls sometimes while stopped at a light. So It's hard to diagnose the problem cause I can't get it to do it while I'm under the hood. So I don't know if the problem is fuel or electrical related. Today though the car started spitting and spuddering while driving and the Check Engine light came on for the first time for about 5 sec then went out. Had it stayed on It may have made finding the problem a whole lot easier. My question is do our computers store trouble codes? Even though the check engine light went out, would I be able to connect a scanner and pull the code or does the check engine light have to remain on to do so??

 

Yep, use a paperclip.

 

Yep, they store the trouble codes, just do like Red Devil said. Take a paper clip and jumper pin "A" & "B" of the ALDL and turn the key to the "ON" position with the engine off. Your fans will come on and is a normal occurrance. The first code will be 12 and will flash 3 times, this is normal. Any codes stored will flash after that. After getting the codes, turn key to "OFF" and remove paper clip and key.

 

sounds like a code 34 MAF problem

 

No MAF on his car, he has the MAP system.

 

a '91. Anyone know offhand which EGR system he's running? Hint...

 

If he is still using it, he should have a negative back pressure EGR on his car.

 

yes have egr still on. Where is the ALDL located??

 

Below the edge of the dash by the drivers right knee next to the center console. It might have a plastic cover over it that says diagnostics. If you have the bolster panel installed under the dash, there will be a small rectangular panel covering the opening for it.

 

Ok just pulled the code and 15 came up. Looked it up and it says that's a coolant temp sensor circuit (low temp indicated). would something like this cause the problems I'm experiencing??

 

That is a good possibility since it sends infomation to the ECM about the temperature of the coolant so it will adjust the operating parameters of the engine. Here is a troubleshooting chart of the code 15 for you to use to find your problem. Hope this helps you out.

 

page 2

 

Yes, the bad CTS can cause stalls if the computer hasnt flagged an error and takes the cts at face value. Basically, the computer will think its cold out and enrich the mixture. Kinda like having a stuck choke on a carb motor.

 

Trickster, you must have every page of those service and wiring diagram manuals scanned into your computer by now

 

but it's not like this all the time, it's an intermitent problem. What would be the most likley cause, a bad CTS or faulty connection. I figured that a sensor like this would go bad and stay bad. Not work some of the time

 

I do, and as soon as it gets here I will be scanning a manual for an 85 trans-am. In about a month, a friend is supposed to loan me his 92 camaro manual.

Grafx,
Since it is only intermittent, I would take a look at the connector on the CTS and check for broken wires, loose connection, corrosion, or a broken pin on the CTS. Pin "A" of the CTS connector is a ground wire that also goes to the MAT & TPS. It may not be the sensor but a bad connection. Use that chart above to check it out.

 

changed out the CTS today and took the car for a test drive. So far, so good. Hope the symptoms don't come back.