Overheating Problems

[janda240sx]

O.K. I've been having this prob. for bout a year now. The car will run fine sometimes and then would just all of asudden run hot almost instatnly. I've chnged the thermostat 2 or 3 times with no luck, radiator, cooling system flush, cluth and clucth fan . Now the thermostat is completely removed (the only way i am able to drive it without it running hot) and it still warms up waaaaaayy faster than what it should. Its not a cracked head or gasket either.(already checked those) Any help greatly appreciated.

[Slappy]

zerothread/288367

[xekushnr]

there could be air in the system, causing it to overheat.

the radiator cap might not be holding pressure, which would cause it to overheat. the cooling system is typically under 12-15 pounds of pressure. I believe 1 pound of pressure equates to raising the boiling point of the coolant 2-3 degrees. if the cap isnt holding pressure, then the car would overheat a lot easier.

the CTS may be malfunctioning. check the FSM for a method of testing it, you will need a voltmeter.

[janda240sx]

O.K. whats the CTS? Seems like thats the only thing I havn't checked and I know theres no air in the system and its not the cap. Got a volt meter too.

[xekushnr]

Coolant temperature sensor. That honestly sounds like the least likely of your problems though. Have you pressure tested the system? Have you bled it properly, according to the FSM?

[janda240sx]

Yea, I've bled it and pressure tested it. Everything was fine. I hve changed the CTS also, I just had a brain fart and forgot about that. w/o the thermostat it runs pretty good until you get slowed by traffic or have to stop. then starts climbing immediatly. Do you think the EGR celinoid valve beeing stuck open could have nething to do with it? Been planning on removing it but havn't gotten around to it yet.