Wierd overheating problem...

[SCOOBYSHAG]

hey guys this is kind of different than what I have read from other guys having overheating issues.

Ok check this out. It is an Sr motor (obviously), with a Koyo aluminum radiator, dual electric 12" fans, adjustable thermostat and FMIC.

This started happening just about a week ago (have had the rad/FMIC/fans installed for about a month now). Strange thing is that it doesnt happen on my way to work or really on my way home, but more on my lunch break and at night. Dont know if that matters or not. Anyway the temp gauge needle will slowly start to rise and then cap out right around the last line before the "H". I will then turn on my A/C and it starts to very slowly come back down to normal (normal being about the middle between L and H). Im not sure why the A/C would bring the temp down but it does.

Like I said also, this isnt everytime I get in the car but just about 30% of the time. I made sure and bled the lines correctly when I first installed the rad/fans. Besides, everything was fine for about 3 weeks and then this started happening.

I thought for a second that maybe my fans were not kicking on and that the thermostat was set at too high of temperature so last night I lowered the temp setting and today at lunch it did it again. Does the A/C automatically kick the fans on or something? Any ideas?

[JJ240]

If you turn on the heat it will flow coolant coolant through the heater core and the coolant lines going to it. Usually you can lower your temperature that way. Stock setup there is a fan connected to the AC but if you installed dual 12" fans the AC fan would have been removed. Check your radiator cap and make sure its sealing good. Did you use a stock one that might not fit as well on the aftermarket radiator? Also check your coolant levels. Is there coolant in your overflow resivoir? If not add some and after you drive somewhere check it every time to see if it dissapears or if theres more in there than what you added.

[JJ240]

Then update us.

[SCOOBYSHAG]

Ok, I will check on that on my way home and let you know. Yes I transferred over the stock radiator cap to the Koyo.

[SCOOBYSHAG]

hey JJ yeah on my way home the car didnt budge over halfway on the temp gauge. Like I said before it happens randomly. Sometimes when I am driving around and sometimes when I am sitting still idling.

Whenever the needle does start to rise though there is no smoke at all and no idle problems at all. Maybe it is the temp gauge, temp sensor, or thermostat?

[JJ240]

Possibly, keep checking your coolant level. Watch the amount in the overflow resivoir. Try a different radiator cap. See if Koyo reccomends anything. Then thermostats are cheap you could try a new one of those as well.

[SCOOBYSHAG]

Hey I checked my radiator and it was a little low so I refilled it. The overflow tank was pretty empty so I put a little water in there also.

Yeah I think I am getting a radiator cap and thermostat this weekend.

[SET240SX]

I had a similar problem couple weeks ago. My radiator cracked and caused overheating. I replaced the radiator for $92.00 and after it did just like you said sometimes it would run fine other times it would get hot. Turned out my thermostat was sticking. Replaced it and now its back to normal. Oh yeah i replaced the radiator cap also just to make sure.

Philip

[SCOOBYSHAG]

sweet. Yeah I am thinking that it is my thermostat sticking also. So I am going to replace it and the radiator cap just in case. I might hook up a mechanical temp gauge also just to make sure it isnt my factory temp gauge acting funny.