I have recently been having a weird problem with my 98 Cavalier(2.2). Once the car heats up if I rev over 2500 rpm it starts cool down, way down. It happens both while driving and while in park or neutral. It's been going on for awhile now, and recently I flushed my radiator, changed the thermastat and temp sensor. The problem is not as great now, but it still cools even when in park. Anyone have an idea what could be happening? To give an idea how bad it was, I have been driving without heat for months, on the freeway I drove 20 miles and the heat never went higher than about 125, now if the heat drops it doesn't go below 150, but the heater loses some heat.
Did you bleed all the air out when you did the flush etc?
Seems as though you still have an air pocket in the system.
Alont
I already changed the thermostat, and yes I did bleed it, and I try every few days to bleed it again, but so far no air is coming out, just fluid. I am wondering now if my overflow bottle cap needs replaced? might be preventing the system from pressurizing maybe?
what kind of antifreeze did you put in? did you mix it well with water ? is it straight antifreeze with no delution with water? or is it 50/50 ?
Eric,
does your '98 Cav have a radiator cap?
I ask because I know some models don't have one.
If it does, you could try the official test from my '93 shop manual.
Remove the rad cap (when cold), start and run the engine until the thermostat opens and a flow of coolant is observed in the rad.
If this happens the fault is other than the thermostat
Alont
I don't have a radiator cap, just a cap on the overflow bottle, and I used 50/50 because it was all I could find late at night when I needed it, so the mixture should be right. It was GM approved and red, Ican't remember the brand but I doubt it matters either.
Are you running out of coolant? if so theres a good chance its not pressurising?
"
boobs now with Riboflabin"
