1999 Suzuki Vitara, 2.0L, 95.000 miles, overheat at idle.
When I stop the car at idle for some time after a trip or when there are traffic jams and it remains idle for some minutes the temp gauge start to reading higher than normal until it reach the red zone.
If I accelerate the car between 2500 and 3000 RPM the temp gauge start down until it reach the normal position, but after some minutes at idle the temp start climbing again.
When the temperature is higher than normal the radiator's upper hose is very hot but the under hose is cold. After I accelerate the car between 2500 and 3000 RPM, and the temp reach the normal level, the under hose starts to be warm and then hot after a minute.
I replace the thermostat with a new one, the radiator was checked and it is OK. The problem rise only when the car is idle for a while after it has been running.
Climb a mountain does not rise the temperature higher than normal, but stop the car or began to lower the hill at idle will do it.
If I remove the thermostat the temperature is always below the normal level. It reaches 1/3 as max when the car climbs a hill but then it decreases to the low position when the car lower the hill.
When the car run without thermostat both radiator hoses are hot, I think there is no problem with the water pump because without thermostat the temperature is always very low.
Some times, particularly on the night, when the car is at idle and the temperature is higher than normal, the calefaction's hot air is cold. After I accelerate the car to lower the temperature the hot air starts to be hot, very hot.
Are the cooling fans working when the temp goes up?Let us know
February, 24, 2007 AT 3:36 AM
This car has a fan clutch system, I suspected a fan clutch failure but the radiator's under hose is cold when the temperature rise to the white/red limit.
Fan is working, I don't know if it is running to the speed it is supposed to be, but the radiator's under hose is cold (I can touch it without problem when the engine temp is in the white/red limit) and it gives me the idea that the new water getting in is cold.
The thermostat is at the end of the radiator's under hose, next to the water pump. It's has been replaced with a original one from a Suzuki dealer but it does not fixed anything.
It appears like there is no sufficient water flow when the engine is at idle, it can explain why * sometimes * there is cold air when calefaction is on before rev to 2500/3000 RPM.
There is no leak at the water pump or at least it is not visible.
After some minutes with the engine temp above the normal level and car at idle I can see and hear the overflow tank bubbling out.
February, 24, 2007 AT 7:29 AM
Ahh overflow bubbling, this could be a failed head gasket causing that problem.
February, 24, 2007 AT 12:13 PM
Yes, the overflow tank is bubbling out but only after the overheat comes. The car didn't overheat if it is running at high RPM, it only overheat if it is at idle for some time.
If I rev to 2500/3000 RPM when the engine is overheating the temperature returns to its normal level and there is not bubbling on the overflow tank.
It don't overheat at idle when I start the engine in the morning, only when the engine has been running for a while and then is idle for some minutes. If the engine has been running for long time the wait time at idle for overheat is lower.
February, 24, 2007 AT 12:46 PM
I would have it checked, heat+metal =expansion
February, 26, 2007 AT 12:52 PM
Today I run the car for a while without t-stat and I can see bubbles in the overflow tank. I think you are right and there is a problem with the head gasket that might be passing air to the cooling system.
Air in the cooling system might cause low coolant and then that could explain my overheat problem at idle.
February, 26, 2007 AT 1:25 PM
Usually when you see bubbles like that there is exhaust gasses blowing through the head gasket making their way to the overflow res where it shouldnt be have it tested
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