Problem starting 2002 Buick Century

I got my mother’s 2002 Buick Century when my Ford Focus Wagon was totalled. It was free, but it’s required more than $2000 worth of repairs. I thought that would be it, but I"m having another problem, and my mechanic can’t duplicate it, so he can’t fix it.

Several times at night when the car has been sitting for several hours and it is/has rained or is dewy, the car starts, but if I take my foot off the gas pedal, it stalls out. I have to sit there for 15 minutes with my foot on the gas before it will hold the start. Yesterday it was hot and muggy (high 80’s, not sure about humidity, but it was very sticky, and I was near the ocean) and it happened again. The car had been sitting in the sun in the parking lot for 3 or so hours. I only had to gas it for about 5 minutes this time to get the start to hold.

Also, when I have my foot on the gas, and rev it, the engine gets jumpy (hesitates) and makes a sounds like uh rrrr. Kind of like it’s coughing, Not a good description, but it feels as if the car is having trouble revving and has to make an extra effort.

Help! I work at night and am often alone in parking lots late. I don’t want to get caught not able to get it started, especially when the cold and damp sets in.

If you have a cold start valve on the engine you might start checking it for a problem. There may be a electrical problem, like a bad connection, causing this trouble.