I have a 94 Z28 6 speed.

I had a new water pump installed last year. Unfortunately, the head gaskets blew at some point so I just had both replaced last week. Also I found out my radiator was cracked. Had a new one installed yesterday and the guy showed me the old one and it was extremely dirty and had a crack on the side, so I figured the new radiator would help as well.

I don't understand why my car is still running so hot it gets up to 3/4 of the way up the temperature gauge. Could my temperature sensor be bad? That would be nice if it was something small like that for once. Any help is appreciated..


Thanks.

 

Has the system been thoroughly bled of air? When does the 3/4 mark get reached, while idling? Driving? Do the fans come on at any point, including when the A/C is turned on?

 

I'm going to try bleeding it and see what happens (this time hopefully I don't unscrew it too much drop the screw and have it vanish into thin air). Also, I have a new radiator cap I haven't put on yet. The old one looked very worn so I bought a new one and I'm wondering if that could be part of the problem. I put in a new thermostat summer of '08... not sure if I'm due for a new one or not... I'm going to check the fans later after work. I believe they are working correctly but I am not positive so I need to check anyway, I'll let you know. Thanks for your help.

 

Remember, stock fans don't come on until 227 degrees (235 for the high).

 

That's correct. That's why I asked under what conditions the high temp is reached. If it's nothing but stop and go traffic, no A/C running, and it's 95 outside, then you'd expect to be at 3/4 on the temp gauge constantly.

 

Oh ok. That makes sense seeing as it's been pretty hot here lately. What is your normal operating temp and idle temp?

 

The OEM guage may not be very accurate... Might want to double check with a multimeter w/ temperture probe...

I have something like this:

 

My normal operating temp is 190, but that's because I always have the A/C on from startup (I'm in Orlando). Idle temp is the same (as long as the A/C is on). If I'm in stop/go traffic in the middle of the day and I didn't have the A/C on, it would be to the 3/4 mark. On my car, the fans kick in just after that 3/4 mark on the dash gauge. That's with no A/C running.

When you approached that temp (3/4 mark) what conditions was your car in? Was your A/C on? If your car is in the driveway idling, and your A/C is on, I'd expect it to hover near 190 which is at/slightly above the 1/4 mark.

 

I know My 96 Z28 runs really hot all the time. I luckily have my radiator fans on a manual toggle switch so i keep them on alll the time when i am driving or i will overheat really bad. On a hot day if i keep my ac on high my engine stays cool.

 

That sort of doesn't make sense. With the AC on, much more heat is added right in the airflow to the radiator. There really isn't anyway the engine can run cooler this way.....

 

but the radiator fans automatically come on and stay on when the AC is running.

 

He stated that he has a toggle switch and keeps the fans on all the time. If that doesn't keep things cool, turning on the AC will just add more heat...without adding more airflow.

 

The way I read it he can use his A/C on a hot day without overheating. Not about the A/C keeping the engine cool.

 

That's my point...it doesn't make sense that his engine would stay cool with the AC on if it runs hot the rest of the time with the fans on. Maybe I'm not explaining it properly...

 

He said he has a manual toggle switch so it doesn't overheat the rest of the time.

It is possible that his fans do not turn on at the correct temp.