I have no idea about cars and would certainly appreciate your expert advice. I have a 1995 Oldsmobile Delta 88 Royale LS 3.8L V6, 103000 miles. I have been recently having some problems with the engine stalling. When I drive around town for short time it runs fine. However, the car bucks and drags when I go on a drive longer than 40-50 miles. I have tried driving it on interstate highways and flat back roads. It seems that, when I give it gas the engine might not stall, but going downhill or something I do have to brake and the engine automatically stalls on me after a 40 mile drive. Then, when I try to start it after the engine had stalled, it starts right back up. I took it to three mechanics so far including a GM authorized dealership.
Mechanic 1: suggested that a complete engine and transmission service would fix the problem. He claimed that he had replaced everything including PCV valve, spark plug wires, spark plugs, fuel filter, air intake system cleaner, injector service, tune-up, transmission fluid, transmission filter kit and transmission service, Trane engine performance analysis (check ignition and emission control systems using analyzer) and charged me $500. This did not fix the problem.
Mechanic 2: suggested that it was a Throttle position sensor and he replaced that at $150. This did not fix the problem. However, he also suggested that the problem could be the PCM computer going bad due to heat. So he put some heat resistant gel on it and slapped it back on.
Mechanic 3 (GM authorized dealership): suggested that the problem was with the pass lock sensor, ignition and cylinder and they replaced everything at $410 and even gave me a new key. This did not fix the problem.
Now I am down to the fourth mechanic (another GM authorized dealership guy), who is suggesting that after checking the power cables, ground wires and fuel pressure, that it is indeed the PCM computer module. He said that the engine stalls when he leaves it running with the heat on at idling state. He also said that he looses all communications with the car when it stalls. The estimated cost for replacing this is around $400.
I need this car pretty bad for commuting to work (around 4 hours twice a week) and my wife has health problems. I cannot afford a car payment. Please advice me on what I should do. Should I go ahead and get it fixed?
I am tired of being hassled by these mechanics who assure me that the problem is fixed then charge me so much and yet the car ends up having the same problem again right after I pick it up. Please advice. Thanks for your help.