Car stalls when it warms up

Questions -
1. Can you expand on what to do with the idle controls?
2. Where is the Throttle position sensor located?

Note - I already cleaned the throttle body, IAC and MAF sensor.

So since I cleaned the throttle body, IAC and MAF sensor, what else should I look at?

What's causing the car to choke and stall when I give it gas?

Will a multimeter do?

Found this:

The main and only item in the tool list is what is called an ohm volt meter. Once you have identified the TPS sensor, turn on the ignition, do not start the car, make sure the volt meter is on twelve volts DC. Locate the connector that goes from the ECM (engine control module) to the TPS. Once you find this disconnect it completely from the throttle position sensor. There are three prongs; the center prong is usually the negative connector.

Once this is done, take the volt meter and connect the negative side (usually the black wire) to the ground terminal on the battery. When this is done take the positive lead, (usually the red wire) and attach it to one of the other prongs. The volt meter should read five volts, if you are on the reference wire for the TPS. If it reads anything below five volts then you are on the signal wire and need to go to the other prong in the connector. If it reads nothing on the volt meter then you are on the negative connector. Once you locate the reference wire, and it reads five volts then you know that you are getting proper reference voltage to the TPS. Therefore you have just eliminated a faulty power feed to ECM.

Questions:

1. Is this the correct procedure?

2. Are they referring to the car battery?

When I press on the accelerator, the acts like I'm revving the engine and then threatens to stall.

If I let up on the gas, the engine settles back down.

Any thoughts?

It is easy to change out the TPS?

I kind of doubt you have a TPS problem. I think the engine computer relies more on the TPS when the engine is cold, but your problem is after the engine warms up. But here's something easy that is worth a try: Unplug the electrical connector to the TPS and try revving the engine in the way that makes it threaten to stall. If it is no better, plug the connector in again and forget I said anything. If it IS better, try driving it that way, up hills where it usually stalls. If it is like my car, your automatic transmission will shift funny while the TPS is disconnected -- mine would not shift until about 4000 RPM. But if disconnected cures the stalling problem, that's a good sign the TPS is involved.

P.S. You said the fuel pressure was checked and was OK. Was the volume also checked -- that is, could the fuel pump maintain pressure when delivering lots of fuel, as opposed to idling or before even starting the engine?

Has ignition timing been checked? (I'm not sure if that is even adjustable with your car, but bad timing could cause problems at higher engine speeds and up hills.)

The puzzle to me is, why did the problem go away for a week after the first shop worked on the car? Did it REALLY go away, or was that just wishful thinking on your part?

No it really was working; I was able to drive it out of state (60 highway miles) with no problems. It ran perfectly for 1 week before the problem reappeared.

Well, I am not a mechanic so I hesitate to suggest more than what I already did. It sounds like the first garage you mentioned is the only one that did any good for the car. Maybe you can go back to them and say, "You fixed the car but the problem came back in a week". Remind them nicely that you spent a lot of money and don't have any left, and see if they offer to at least check it again to see why their fix didn't work.

You're NOT a mechanic? Then what are you doing on this forum giving car repair advice?

Is there anyone there who is, who can help?

Please pass me to a certified mechanic.

I tried what you suggested -

"Unplug the electrical connector to the TPS and try revving
the engine in the way that makes it threaten to stall.

If it is no better, plug the connector in again and forget
I said anything. If it IS better, try driving it that way, up hills"

Result:

1. The engine idle was much higher - stuck in the 2000 range

2. My brakes stopped working - they got spongy and not stopping.

Thanks for taking over. I've seen your profile; are you well versed with Chevy cars?

I do not own a scan tool nor can I take it for a spin because it stalls.

Questions:

1. If I had a scan tool, can it be used with the recalibration?

2. What is the procedure for doing a recalibration?

3. Would it be easier to just change the TPS?

Welcome back