My 95 is running hot. Quircky hot. Gauge sits at 200 most of the time. Then suddenly jumps to 280. Sits there a minute or two, then instantly jumps back. Other times it will creep slowly up into the red zone, then fade slowly back down to 200. This has been going on since last summer but rarely in the winter with outside temps cold. Now it'* becoming a big problem. Car has never overheated, boiled over.
Last fall I just thought the gauge was acting up, the way it was going crazy, but I don't think so anymore.
Here'* the dirt.
> I'm original owner, flushed and filled the car many, many times over the years.
> I change the water pump two years ago. Big PITA. 10 hours in freezing cold weather.
> Radiator is original. Never had issues. Everything flushes clean, fins, tank etc.
> I decided to change thermostat, rad. cap, and CTSs, even though they were not old. They had no effect.
> Cooling fans don't come on properly, I have manual override switch but it does not change the fluctuating temp one bit. Sometimes engine gets hotter when I turn the fans on.
> No leaks, no coolant loss, no weep hole drip, and water pump pulley is tight & smooth spinning.
> Upper rad. hose gets hot, but not too hot. Lower rad. hose stays cool most of the time... every once in a while it gets really warm. Radiator stays cool, never getting really hot to the touch.
I think I have a flow problem. Comments appreciated here.
I don't have a scanner, but I don't really think the CTS and PCM numbers are all that relevant, considering the lower radiator hose is often cool to the touch.
> I can check the flow through the radiator without much hassle, but the only other component to screw up the flow is the water pump. Right? Is there a way
to check its flow production without removing it? I hate that darn thing.. PITA.
I know the impellers can come loose etc. but I want to be sure
before I go through that again. :(
> Would a head gasket issue stop all coolant flow? I do have a little bit of oil appearing
around the head gaskets, but not enough to drip or even smell.
> Is there something else I'm overlooking?
Kind of long explanation. I've done searches, most point to WP or radiator if it'* a flow problem.