I have 1991 Firebird Formula 5.7 TPI. The car overheats on idle and stop and go traffic. This oil will drop to low (near zero). The car got near 250 in city driving and hate to get cooled off. In open highway acts fine. When you get back on the gas the temp goes back down and oil pressure returns. When parked after driving the oil gauge will look like the tachometer, when you rev it goes up and backed down. We replaced thermostat, radiator cap (the radiator is new to begin with, no leaks), no oil in coolant or coolant in the oil so its not a head gasket. I ran it on my buddy's scanner it gave us codes for the knock sensor, esc module, and egr valve. I don't think thats it though. Just noticed one of the fans isn't blowing (dumb and saw one moving and just assumed both were) so I think thats the overheating issue. The engine sounds perfect and drives just fine and is in too could of condition to lead to the bearings (course I could be wrong).

Just curious whats making the oil pressure drop off. Could just be the heat, but haven't fixed the fan yet to find out. Just wanting some opinions of those smarter than I am.

 

For the temp...factory fans will kick on about 225* by themselves. If you have dual fans, one fan will turn on with the A/C turned on. Both should kick on at 225*. I only have one single fan so I'm going on memory for what I've read. Best to do a search on the forums and you'll find out for sure.

FOr the oil pressure, make sure your sending unit wires are away from yoru spark plug wires. Mine got close and were causing my pressure gauge to jump around. Not sure on why it would stay low though, unless you've got a faulty sender.