I have a 1995 Monte Carlo z34 with a 3.4, and I have been have a couple of problems that I hope I can get some opinions on.

1. Only when I am stopped. The car will rev up and down and serge, like it wants to die, but when I'm driving it runs fine.

2. My low temp light will not shut off. I changed the water pump, T-stat, and the radiator along with the coolant level sensor. The only thing I haven't changed is the resivoir tank and the radiator cap. I can't drive more than one mile and the temp gauge will be at the half way point. Soon after that, the temp gauge is pegged out and the car is running hot to where the car is stalling. Even though it's running hot and stalling, the radiator cap is not hot. I take off the cap and there is pressure in the system, but water is not flowing out like it should when a car is over heating. It's like the water is not flowing to cool the engine, but the radiator seems to be flowing.

Any help, ideas,or suggestions I really appreciate. Thanks.

 

The surging issue - check your IAC valve, could be sticking. Also check all your vacuum lines for a leak.

I too have that very same low coolant light, changed the sensors and it's still on... Just make sure you have plenty of antifreeze.

 

I have a 1994 Lumina Euro Coupe with the exact same problems. I changed my Coolant line, the preformed one from GM that cost $300, my water pump, and T stat. Fixed the Coolant prob but the Surge issue is a sensor and I cannot for the life of me find out what it is. When i take it to the shop they run there tests and it says it is fine but I know it is not.