Overheating questions.

[adampad]

My 2003 P5 has never had any issues until now. The car is overheating. The CEL came on and I had it checked. It said the coolant temp sensor was bad.

Can a bad temp sensor cause the overheating? Should I try putting on a new thermostat before the temp sensor? When I took it for a test drive, it didn't seem to overheat until I started to get to higher rpm's. Then instantly it shot up. The coolant was boiling and overflowing from the coolant reservoir. Also after I turned off the car I noticed the radiator fans where not on. Shouldn't they be on even if the car is off if the car is hot?

 

[njaremka]

if the temp sensor is bad, the ecu will not know to turn on the fans, and this will cause the engine to overheat. i would replace the sensor AND the thermostat. (thermostat too, since its a $12 part)

 

[justanothermp5]

yea dont drive the car anymore until you get a new coolant temp sensor
if it over heats too much then you could warp your head and then u may need a new engine

 

[adampad]

Well I changed the temp sensor and the CEL went away. However, it still overheated after a little while (seemed to take longer). Only seems to overheat if I get up around 4k rpms. Seems to go down a little while idling.

Keeping the heater going full blast seemed to help it too.

T-stat is going on next. Hopefully that will do the trick.

 

[JDMJNKY]

T-stat is the problem nuff said.