92 olds 3.1 idle & stall problems

Quite possible that it's ignition-related - sometimes it seems like they will increase the idle speed if it detects that the engine speed is too unstable at the lower idle speed (i.e. because of a misfire).

Other than that, I'm not sure if this engine uses a mass airflow sensor or not, but if it does, check that the intake air ducting is not split or cracked anywhere, that could allow air in that's not being measured by the sensor.

Was told by the clerk at the parts store that it does not have a maf sensor. According to Chiltons it should have one and it would be on the breather box. However, the only thing I find on it is the air temperature sensor.

"> Why would it require me to press the accellerator to get it to turn over?

There shouldn't be any connection between the starter motor and gas peddle. if you turn the key to start and get no starter action, then check the starter system. Ignition switch---neutral safety switch on an automatic--starter solenoid---starter--battery cables--battery---engine grounds--wiring circuits. You have to check while the problem is ongoing.

On the idle problems, the general procedure is to clean the throttle-body, first and then proceed from there. If a sensor is suspected, you have to check the sensor wiring also. Don't replace a sensor without checking the sensor circuit.

If your going to trouble-shoot the problem, I think you need at least, a fuel pressure gage and dvom. And that may not be enough. Did the vehicle list any trouble-codes? Did you check the fuel pressure while the problem was ongoing?

When somebody suggests a faulty part, those are just suggestions, you don't replace the part, you check the part and circuit where applicable and proceed accordingly. Don't replace any part I suggested, test them.

No, there have not been any codes stored. I was told by the repairman that the fuel pressure was running at 46 psi when I had the fuel pump replaced about a month ago. As I said, I didn't physically clean the throttle body, but it did not appear to have any gunk in it. Maybe it is where I just can't see, but the intake area and around the iac valve seemed to be clean, though the IAC valve did have some carbon (?) deposits on it.

I agree that it is better to check the part and circuit. There are times, though, when the cost of a part is minimal and you are in a hurry so you make the change without testing the part...not ideal, but sometimes necessary to try to see if the problem is solved.

Robert

I have replaced sensors without checking the circuits, for the same reasons you gave. And I always tell myself, I'll check the circuit next time.

As far as idle speed controls, there is a site at

Correct. They stopped using the MAF on the W bodies between '88 and '90. My father in law's 88 regal has a maf... my '90 grand prix does not.

I did buy some throttle body cleaner and gave the t-b a good cleaning this morning. It's funny that everything I do makes the car run better. I've noticed a significant improvement in it when it appears to be running properly. But, all that said, it still seems to be trying to hold onto what I think is a high idle when I remove my foot from the accellerator.

Robert

Can someone tell me where to find the TCC connection on this car? My understanding is that one should be able to see it from the top (assuming that it is similar to the 91 Lumina.

If I'm standing at the front, looking into the engine compartment, I see the following on the front. On the left is the oil filter. Next to the oil filter is the oil sender unit. Then there is a connector of some sort. There is a little "lip" to the far right with a connector on the top of the lip. This connector has three wires going to it, but as near as I can tell it is a grounding block of some sort rather than a sensor. At least it does not have the protective end found on most of the connectors and it appears that all of the wires are going into one larger pin area, but I could be wrong.

I would like to try disconnecting the tcc to see if that solves my problem or not.

If the car has idle problems when not in gear, or fails to start properly, the TCC is not your problem..

I think the inability to start problm is cleared up, as a result of cleaning the throttle body. But it still seems to idle high, or have a high rpm, when I slow down from high speeds. If I stay under 35 mph it usually slows down fine, but once I high somewhere between 35 and 40 and try to slow down the rpm won't lower as I lower my speed causing it to attempt to run rough and try to stall.

So, I would like to try unplugging the TCC and see if that clears up the problem.

immediately.

Does it clear up if you put it into neutral? If not, then it won't be the TCC. Generally, when the TCC sticks engaged, I believe it stays engaged all the way, therefore when you stop the engine speed is forced down below idle and the engine will stall if left in gear.

Is this the 3-speed transmission, or the 4-speed with overdrive? If it's the

"Robert Sanford" wrote in news:3f00bdc6$1 snipped-for-privacy@corp.newsgroups.com:

"Robert Sanford" wrote in news:3f00bdc6$1 snipped-for-privacy@corp.newsgroups.com:

Here is something you might not have checked. I have 96 cutlass that had a stalling/hard start problem and it turned out to be the fuel pressure regulator. I replaced the tps and cleaned the iac before finding raw gas in the fuel pressure regulator vacuum line. It was a $50 part for my 3.4L. No codes were set and I put up with it getting worse for about 6 months before noticing the fuel in the line. The vacuum line was a loose fit and I only noticed it after putting a clamp on it, which stopped the evaporation and allowed me to see the leakage. I think you should also check for intake manifold gasket leaks by spraying carb cleaner around it while running. I would be interested to hear what you find. Good Luck - Ken