False Temp Reading
Problem: Temperature rizing to 240+ quickly, few minutes and fluctuates up and down often. Must be false.
I changed:
- Thermostat
- Bottom hoze and re-routed
- Temp sending unit
- Radiator Fluid - Orange fluid
I checked:
- Temp of engine by touch and with a hand held heat gauge
- Fans
- Debre, bags, leaves, ...
- Looks as if the engine is using the water because the radiator reservoyr has movement
- Heater works fine
- ATI Supercharger
- Large radiator
- High output Spal Fans
- Big Mouth Air Damm
Whats left? Could this be the gauge itself, air in system? Any tips on removing the air out of the system.
This is crazy.
When I refilled my radiator, before starting I kept adding fluid and massaging the upper and lower RAD hoses until I no longer heard the air bubbles in the line. It worked for me. Try this with the front end lifted. Sometimes the air gets trapped in the engine.
But I'm leaning towards the fans blowing the wrong way.
Run the car up to max temp and open the overflow slowly to get air out. Do it a few times.
IM QUIKR:
Fans are pulling (verified) and I am using the A&A setup. I will try to remove air as you suggested.
Brandon:
No sign of bad water pump, clogged radiator, or blown head gasket. The car is 2002 with 21,000 miles. Not long ago I went to the car wash and flushed water through the radiator with the high presure hose and it appears to be clear of debree.
Quick Silver:
I used a hand held infra-red temp unit to get measurements along with putting my hand on the engine. Thats why I think my gauge is a false reading. I will also try to get any air out by the method you mentioned. I'm not sure what you meant by "Cluster Freak Out". Whats the cluster?
If it fluctuates a lot then it's probably the wiring leading up to the sensor. The sensor is simply a resistor whose resistance changes based on temperature. The PCM sends 5v to the sensor and measures how much voltage gets returned.
I had a wiring problem a long time ago that resulted in the same situation, erratic coolant temp readings. It even made the car run like crap because the PCM alters timing based on coolant temp.
I removed some of the air out of the system as suggested earlier and the car is running at a steady 208-210. When I shut the car off, moved stuff around so I could get it in the garage, then restarted it was at 234.
I'm guessing this is normal, though it was only in the 80's today and it still seems a little hot. Maybe I did not get all the air out.
I get a couple of drips of anti-freeze, can't tell where it is coming from.
At least the panic is over - still a little concerned.
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