92 leSabre wont idle when warm, please help me diagnose.
 

Whats up guys! I'm trying to help a friend diagnose a problem with his 92 buick lesabre. The problem is kind of weird and I've been thrown for a loop with one of the check engine light codes I got. Here's the problem from the beginning:

A few days ago the starter went out on the car, no problem 100 dollar part and a couple hours on my back and that was taken care of. When the starter went out the car was running really rough and lost all power, then died and wouldn't even try to turn over. (Personally I think the starter is just a coincidence, but you guys are the experts, so I'll let you all decide.)

With the new starter in the car it would start but was still running very roughly. The RPM gauge would jump up to 1000 RPM and then drop back down to 0, leaving the car to die. Giving the car gas would keep it going but it sounded really bad, lots of sputtering and coughing and the RPM gauge bounced around a lot. The next morning we tried it again and it started up fine and ran as well as can be expected for a car with 240,000 miles on the clock. My friend drove it all morning, came home and let it sit for a little while, came back out and the same problem, the car wouldn't idle.

A couple of random things to note. For a while now the car has been guttless until it gets warmed up. If the car was really cold they could put there foot to the floor and it still would not accelerate.

I pulled the check engine codes by jumping A and B together like it says in the haynes manual and got the following codes: 21, 24, 48 and 58. I have not been able to find anything that gives me any info about code 58, and I'm sure that its 58... I checked it four times to be sure.

Anybody recognize this problem? Where else can I look?

This is what I'm coming up with and the throttle position sensor is a likely cause of your problems.

Have you tried to reset or clear the codes, try to start it and then read them again to see what comes back ??

DTC - 21 Throttle Position sensor error (signal high)

DTC - 24 Vehicle speed sensor error (open circuit or no activity)

I can't find a 48 ??

DTC - 58 Trans fluid temp sensor circuit error (low voltage)