Car: 2001 Chevy Venture 3.4 L - 100,000 miles on odometer
Issue: I bought the van in january 2009. I am not sure what the correct behaviour of the temp gauge should be. When it has ran for a while (20 minutes or so) it will reach what i think is normal operating temperature (about 1/3 on guage). If i sit in traffic, the temp will creep up to about 2/3 of the guage. When i step on the gas and take off, in will go back down. It seems to vary like this. It has not gone in the red zone yet. If i am driving on the highway, no issues, temp always stays at 1/3 of the guage. I get off and stop, temp creeps up.
Symptoms: Seems to me the fans don't come on, unless it is programmed at a higher temperatire. No check engine light, no codes, no symptoms (hot or cold). Easy to start, both hot and cold. No sounds.
I have plenty of heat, plenty of cool air (a/c)
Tests i have done:
1. pull the plug from coolant temp sensor, both fans turn on high speed
2. turn on A/C, both fans turn on low speed
3. coolant full (dexcool), no evidence of leaks. Inspect all hoses
4. thermostat works. I can feel coolant flowing
5. Water pump pulley is fine. Belt in good condition.
6. getting 5volts at the sensor when cold.
7. resistance appear to be in spec when hot and cold. Except i do not have a temp gauge.
Repairs done to date: 70-80,000 intake gasket changed
Questions:
Is it normal for the temp to fluctuate like this on these vans?
What can i look for? What tests?
Is it possible that the sensor signal may be slighlty off specifications?
How hard should the rad hoses be when i press on the and the system is pressurized?
Answer there could be air trapped in the system if it was not properly purged when the intakes were done, other than that i would see if you can check the actual temp of the coolant with a termomater just to make sure the gauge is reading correctly. Other than that you could have a radiator that is on its way out or debris in the fins of the radiator
