1989 pontiac grand prix

[joshua12345]

hi i have a 1989 pontiac grand prix and it seems to have alot of fluxuation inthe temp gaugeusually under 50km/h it get up so hot the fan kicks on and seems to take a lot of time too cool down but sometimes i step on the gas and it cools down really quickly but have a cold thermostat in it and i dont think it should be running hot like that but sometimes when i shut it off and i turn the key back on its overheating a little bit the antifreeze is green and theres no anti freeze smell out the exaust no loss of anifreeze it runs awsome and i just put a new water pump heater core and the rad was replaced awhile ago but a used one and the thermostat is new and its still running hot got lots of heat in the car its seems to cool down a little at idle but not tha much have no clue whats wrong with its even got a new timming chain and rad cap still not working right

[Ridenour]

First of all, learn how to use puncuation - it's your friend.

My guess would be the thermostat. I've heard of issues with cooler ones - get a new stocker and try running it with that in it. Hopefully that will solve the problem.

[joshua12345]

i replaced the thermostat and still the same problem. my spark plugs are a little white and not brown. but im not loosing any anti-freeze any where i heard that it could be running lean and that could be why its running hot, is that possible

[Beaumont SD]

Originally Posted by joshua12345

i replaced the thermostat and still the same problem. my spark plugs are a little white and not brown. but im not loosing any anti-freeze any where i heard that it could be running lean and that could be why its running hot, is that possible

try bleeding the heating system again its really hard to get all the air out it has three bleeders on it and you have to bleed them until the problem stops

[JimmySLS]

Have you tested the cooloing temp sensor? I had an 88 grandprix and mine was doing the exact same thing..I changed the sensor and it was fine after that..