Have a problem with my '95 LT1. Changed out the coolant Thursday. Drove home to Seattle (about 30 miles, 60 degrees outside), no problems. Decided to stop by Taco Bell on the way, and as I pulled into the parking lot, I saw my temp peg out. Shut it down, turned on the fans, let it sit for a while. Got it to about 180, started it to drive home (couple blocks), and by the time I was out of the parking lot, was pegged again. Shut it down, waiting for a red light. Green light, got about a block, and temp said was around 180 (normal for me). Two corners later, temp was back up. Turned on the heater, and it worked for a few minutes. No longer does. Just blows cold air. If I let the car idle for more than 5 minutes, temp goes near 260. If I pull the radiator cap off, it seems to be ok, temp wise. Put it on, and within 2 minutes, overheats. Checked thermostat, and its good. Not really sure what to do. Any ideas?

 

Hmm, im surprised it's not the thermostat. How did you check it? Water pump maybe? Clogged radiator?

 

When I pulled the thermostat, it was still open. Watched it close. Put it back in, and it opened. Went and baught a 180degree, and same thing (had a 160 in there). Sunday night I'm gonna try messing with it. See if I can see coolant flowing. Might try to make it down the street to a shop and have them flush it. Worth a shot. If that doesn't work, time for a new pump maybe? Really don't want to fork out the money for one right now.. gonna have to wait until Thursday night, about 9pm to order one. Not like us military guys pay attention to paychecks or anything.

 

I just had the same problem. It was the water pump.

 

better cross your fingers and hope a head gasket hasn't popped.