1996 Camaro Z28 heating problem

Hello Guys,

I'm a newbie here and let me just start by saying that it's really great to see everyone helping out! :-) Just for the tought.

Now to my problem...

I have 1996 Camaro Z28 (75,000 miles) and except for that heat problem, the car performs really great.

Recently I had to change my leaking water pump, as I kept on getting a low coolant signal.

After the operation, i noticed that my car's "rest" temperature (i.e. Neutral, no A/C) is at 120. If I drive it for a few miles, I get the temperature rising to roughly 140. And then, after that if I get stuck in a traffic jam the temperature keeps on going up and even climbs to 220-240!!! I noticed that if I put in in Neutral, and gives in some throttle, the temp IMMEDIATELY drops to 140. After taking my foot off, the temp starts climbing back to 220.

Any clue ?

Thanks for everything guys.

Probably have air trapped in your cooling system.

Make sure you bleed it properly from both bleeders.

i'm gonna have to agree with the last post. That is exactly what happens when you have air trapped in your cooling system what it is doing is blocking the coolant from returning to your radiator so when you give it some throttle your water pump is turning faster pushing that air right out into your radiator so your engine cools down again and eventually makes its way back to the blocking point again.

Thanks guys!

One question, If I leave the car overnight, open the radiator cap in the morning and fill it up to the top, close it back. Would that leave any air inside?

Really appreciate the help.

One more question.

What's the "Normal" engine temperature for an LT1 ? I can't seem to see an agreement on that?

I know that it should be related to a country's weather, but any rule of thumb for that?

You will have to bleed it to get the air out.

The car shouldn't pass the 1/4 mark temp wise.

hey bub,
you have to fill your radiator up then start the car and leave it running meanwhile filling the radiator as it needs it then put the cap back on, leave it running for a little while and shut the car off. Then you must bleed it, to bleed it you just have to take a screw driver and find the little blow off valves in 2 of your heater hoses and let the air out then repeat the process. :evillol:

Hello again,

Thanks for all the help guys,
Let me update you on my problem:

I went back to my garage, and put the car on the scanner. The scanner shows a coolant temp of 230F (110C). There is no "bubbling" sound and the coolant light is not on! (It goes on when I turn the car on and goes back off so it checks fine). The guy at the garage says that 230F is a normal temp and that the temp gauge is faulty and needs replacement.
Is 230F normal on a hot day and A/C on?

The water level in the car is pretty ok, everything looks fine. I'm just concerned about the heat gauge and the scanner reading. What do you say?

Thanks.

Guys.

To update you, we checked the coolant temp. on the scanner, and there was a 10 deg. mismatch... It turned out that the gauge is indeed faulty... I'm trying to find one now.

FYI.

The normal operating temp for the LT1 is from 195 to 230. Your cooling fans should kick in at about 229. While driving you should expect to see your temp get up to about midway on your gage (which is about 210), on a hot day. At an idle, the temp should increase until your fans kick on ...and then the temp should drop.

If you temp exceeds 230 and your fans don't kick in, it could be the relays. There are three of them which control your fans

Thanks for the numbers!

Hello everyone.

I'm still having that overheating problem, I changed the water pump, put a 195F thermostat, and the low coolant signal is not popping up.

The scenario:

I drive the car for 30-45 minutes, 60mph, everything is smooth except for one thing: The temp gage shows 160-170 (litteraly all the way down on the gage). So far so good!

Now, I start climbing. 10 minutes later the heat goes up all the way to the middle (around 210F) and sticks there, but once I reach my destination or slow down, the temp quickly jumps all the way to 230-240 and I have to either drive fast or stop the car, put it in neutral and keep the rpm at 2000 to keep it from reaching red. if I raise the rpm to 4000 revs, the gage goes immediately down to 210 but if I take my foot off again, it goes up... And coolant starts spilling out from the coolant bottle.

I really tried everything and I'm starting to think about selling the car!!! I love it but can't keep up!!

If anyone had a similar problem and fixed it or has any clue, I would appreciate it. PS: 1996 Z28 LT1.

Thanks guys.

Hello Again,

Looks like no one faced this before :-( Could anyone direct me to another forum where I might find a solution ?

Thanks guys.

Hi There Just Been Reading The Thread About Over Heating Problems Did You Ever Sort It Out And If So How ?
I Have Exactly The Same Symptoms On A 1996 Z28 Any Help Would Be Appriciated

ive never heard of a car overheating at idle, that cools off when you increase the rpms... are your cooling fans working????? you say you put on a new water pump, so im assuming thats not the problem. if it was an old pump i would say the impeller is worn out, and you have to increase revs to move any coolant. so at this point im thinking your cooling fans are only working when throttle is applied, as to why they would do this, ill have to think on that one. also when topping off your coolant, try this, have the engine running with the cap off. and fill it as far as possible with the engine at idle. once you do that, have someone bring the revs up, this will bring down the coolant level, top it off, increase revs some more, top off, increase, top off, till they are running around 1/2-3/4 throttle. then without slowing the engine, tighten the cap on and then let the revs down. this will put as much coolant in the system as possible, and limit the ammount of air in the system.