1990 Pontiac 3.1. Starts fine when COLD.. but after taking a trip and parking it.. stalls when put into gear..

Question

1990 Grand Prix 3.1. The car starts and drives fine till I arrive at my destination and park it. When I go to leave it stalls when put into drive unless I give it a good amount of gas.. and will sometimes stall at low idle AFTER it has stalled from going into gear. I UNPLUGGED prior to this the torque converter solenoid (which fixed the transmission shaking problem) so I dont think its that. It idles fine normally so its not an IAC. I got a code 23 which is either a bad Air Temp Sensor or a bad MAP sensor ( I dont have a book and found websites that have different answers, can anyone confirm what a 23 is? ) Im going to guess its more thank likely a bad MAP sensor...but I really dont know which is why Im here asking. This problem ONLY happens when its warm and MOSTLY when going from P to D... but will sometimes die while rolling at low speed and not giving it gas even if I am going faster than idle (ie my driveway is a hill and it died coming down it )
Thanks

Answer 1

sounds like your starter is going bad.

have it checked.

Answer 2

It's likely a sensor or switch somewhere. You don't indicate what year & make of car you have, but the mass majority of cars in the last 20 years have "electronic" transmissions that communicate with the engine. When you change gears, the engine & transmission communicate with each other, unlike older cars where the transmission simply does what you made it do. If the engine & transmission aren't communicating properly, the engine won't know what to do and therefore will just shut off for your safety's sake. Don't try modifying components on your car like some here have suggested - take it to a qualified mechanic [in situations like this, it's best to leave it to the *auto manufacturer* since they know the car up one side & down the other, unlike a general mechanic who is a jack of all trades -no offense as I use mechanics when & where applicable] and just get ready to pay some money for a proper diagnosis and repair. The dealership will let you know what they found out, and how much it will cost to repair it. You may get lucky and find out it's just a $25 switch or sensor that has gone bad. Along with the diagnostic fee and labor, you could get out the door for under $200. In today's cars, you can't just go chopping things up yourself. You'll only make it worse. Good luck~

Answer 3

temp sensor