Cooling help
 

I just put a new radiator in my 95 camaro 3.4. Now the heater doesn't work and the temp guage fluctuates up and down between 180-200. Searching the posts here I think its a clogged heater core. I'm going to take it to the shop and have the system flushed out. My question is am I damaging the engine at all by driving it?

are you sure you got all the air out of the cooling system? Low coolant levels could give the symptoms you're describing as well.

As long as the engine isn't overheating I can't see harming it driving it like you are, but keep in mind in the factory temperature gauges aren't accurate on these cars.

Make sure it's bled properly. If so, it's fine to drive it in the mean time, but keep your eye on the gauge.

My truck had that problem with the heater and it turned out to be the thermostat so I'd check that to see if maybe it's stuck. truck also had the fluctuations you were referring to.

Had the heater core flushed and a bunch of rusty crap came out. Heater nows blows warmer air but not hot. The mechanicn said the core's probably pretty rusted and needs replacing. I live in the desert, so I can fix it later:) He did mention that the thermostat might be bad, but I just replaced it 6 months ago. Would it go bad that fast? Is it the right type??

The LT1 takes a specific thermostat that is different from the standard small block Chevy.

hes got a 3.4, it takes a regular style thermostat... To answer the OPs question, yes, the themostat could be bad already if they flushed the system, it could have gotten clogged up.

To answer your original question ---- On the left cylinder head (drivers side), on the side close to the front, there is a temperature sensor for the gauge on the dash. Take that sensor out while the engine is cold and procede to fill your radiator untill it starts running out the hole. ***Might be a good time for a second set of hands if you have someone around that can help*** When it starts pouring out, put the sensor back in and continue to slowly fill your radiator, let it sit with the cap just sitting on it, not actually closed, for about 30 minutes or so. It should bleed itself off a little more once you get to that point. Top off again and go ahead and start it with the heater on so it can cycle through everything.

If you have any doubts at all about your thermostat, go ahead and change it, put a failsafe in for piece of mind. Now would also be a good time to add an aftermarket temp gauge while you've got the dash gauge sensor out of the head.

Driving it with it not bled off all the way could cause problems, depending on how low it is, you will have large air pockets and hot spots. Not good.

If you run into any problems post back and we'll see if we can get ya fixed up. I will say though, putting an aftermarket temp gauge in mine was one of the wisest things I've done with this car. Dash gauge is a joke, as you can tell.