93 Camry Has Just Started Radical Heat Guage Readings

Next time this happens pull the heater lever to full hot and fan to full. Open window to avoid overheating yourself. Watch for the temp to drop. If it does you may have some kind of blockage in the radiator or a bad thermostat or a collapsing lower radiator hose. Squeeze the hose to see if it is too soft. I assume you have ac so you cannot feel the front of the radiator for hot and cold spots( a sign of blockage).

-- Richard N. Price

aware

The Ford van I just replaced did that once. Seems like the thermostat had a mind of its own. I replaced the stat with a new one (get OEM or Stant brand, no cheapies), flushed the rad and refilled with a 50/50 coolant /water mix. One or all of the above fixed the problem. FWIW YMMV DFB For email remove "_no_spam_"

aware

Sounds like the thermostat has gone bonkers, tho they usually show up as either not opening sufficiently on warm-up, causing overheating, or, they slam shut and stay that way.

I'd be checking the gauge is actually showing the true situation with engine coolant temp. If you can get an alcohol temp-gauge (and they are available in those cheaper after-market places). Drop its bulb into the top-tank when your gauge is in the red. Mind you, you will need to be *very* careful when undoing the radiator cap. Use an old jumper or equally large, thick piece of clothing. Better still if you install it permanently to give you a continual coolant temperature regardless of ignition key position.

Jason

If it's happening only with highway driving say after 20 or 30 mins, it is probably a blown head gasket. Continous high speed driving is where a blown gasket is going to most likely show itself. What is the mileage on the car? You may have damaged the gasket from overheating due to a cracked rad/fluid loss? Are you losing coolant? As well, check your water pump or other areas like the rad, hoses for leaks.

davemac

He said he wasn't losing any coolant. If the gauge was actually reading correctly ie his coolant was going to very hot,.you'd think his expansion resevoir would overflow, then show as low or empty when cold.

Jason