Overheating SOMETIMES please help

[bonzo666]

ok guys heres my trouble

have an over heating issue. replaced the thermostat but problem persists.

here is the funny part...i know its going to start over heating cuz the heater temp gradually reduces in temp and needle spikes to H.

if i get the engine revs back up to 3500 the air gets warmer then hot and temp needle drops back to normal.

could this be something as simple as the belt or is it the water pump?

anybody have a similar issue????

Your help is sooooo appreciated

 

[erhayes]

Check your cooling fans

 

[bonzo666]

Check your cooling fans

Sorry, should have mentioned fans are running. At least they are when i get out to check them. I assume they are running when the car is moving. In fact i can hear them when stopped at a red light.

Coolant level is good. Oil level is good. Just really stumped.

The only thing I can think is either the belt or the pump because it seems circulation of coolant gets better with higher RPM. AC seems to be working fine to so I kinda ruled that possibility out as well.

This is driving me crazy.

Commuting to work this morning, I had the heat on and as the temperature of the heat started to decrease I would increase RPM by staying in 5th gear and heat would come back. Engine temp was bang on as long as I stayed in 5th gear. My commute is approx 50miles.

Really weird

Again, anybody have suggestions or similar experiences???