Oldsmobile/Buick Repair: 1994 olds achiva coolant problem, temperature guage, coolant system

Question
Van,
I have a 1994 olds achiva, it has a 4 cylinder, quade 4 engine.
my problem is that before the repairs i just recently had done the coolant would get hot after about 30 min of driveing and it would red line
on the temp gage, then i had to turn the heater
on to help cool the engine temp gage would show it cooled down
i brought the car to a repair center and thinking i needed a radiator or thermastat in stead they said they were reading hydro carboms in my coolant system and recommened a head gasket change.
i did the change but it didnt resolve the problem
so they replace the radiator, thermastat, temp switch, fan relay and water pump, after all that it still not right, its better but not right. when driveing (50mph)its register about about 220 on my temp gage when idleing it go up not to the red line but it moves up, i also notice that my oil pressure gage fluctuates alot too, it use to hold at one temp now it up and down, they replaced that switch too.....what do u think problem could be?

Answer
Hi George,
There is a possibility that the fround wire from the engine to the firewall is loose or missing, and the gauges are just not reading correctly.
A mechanical temperature guage is the way to see what the temp actually is.

If there is still hydrocarbons in the radiator neck, you could have a cracked head.

Van