Hey guys. I posted earlier about a possible bad head that was making my car overheat and bog. It's a 94 z28 with only 37000 k on it. The first mechanic i took it to only had it for 3 hrs. He told me that he was possitive that i needed new heads and that it was gonna cost 2k to fix. I was skeptical so i asked my friends dad who is a mechanic to look at it. He says that i don't have bad heads or gaskets. The temp gauge shows its extremely hot, but the heat sensor he uses on it says its not. Heres what is going on:

First, the AC compressor switch is malfunctioning and stays on all the time. So the entire time i have had my AC on without knowing it. This could be why it bogs and overheats. Secondly, I had sensors unplugged near my intake. They're plugged back in and shouln't be an issue. Also, the cooling fans don't come on.

So if any of you have overheating problems, check the ac compressor. In my case, it was spinning even with ac turned off. I had to unplug the switch.

Also do any of you know know why the gauge, ac, and fans could be malfunctioning. Could it be a bad ground? I'm gonna get a good code scanner. Any recommendations? I know they're like $1k, but i need one to clear the codes that all this stuff has probably brought up.

Anyway, after unplugging the ac switch, it didn't bog even when the temp gauge was almost in the red. I need to figure out how to fix the switch, the fans, and the gauge.
thanks

 

[&:]couple of things to keep in mind. the compressor clutch also is on in any of the defroster modes as well not just ac settings. also the fans for these cars dont come on until about 220 deg( right next to the red zone on the gauge). kinda scary but thats how they're designed. the cars should never overheat even with the ac on unless there is some other shortcoming, period. they are designed with the necessity of removing the heat from the engine and ac system even in the hottest of temps. id recommend leaving the scanner in the professionals hands as ive stated before they are only a direction helping tool and should not be thought of as a magical box that tells you what to replace ( ask any tech that thinks that and he'll show you a shelf of perfectly good parts hes installed and then had to remove ) as the old parts worked just fine. id recommend the dealer as they have the most experience and will most often NOT just be parts replacers as diagnostics go like small shops often are kurt