96 H22a. about 3 years ago i had a similar problem with the car slightly overheating while sitting still. replaced the stock radiator and fixed the problem.

about 2 or 3 weeks ago it started overheating again. now it doesnt matter if im moving or sitting still. if the engine runs for 10 mins or so the temp gauge will be at the redline. my coolant levels are fine and i doubt its a radiator problem.

i found it kinda strange that my fans dont turn on anymore. i was letting the car idle in my drive way and even when it was overheating the fans never turned on.

so i turned the AC on once i had like 4 bars and forced the fans on but the engine didnt cool down, it proceeded to redline! perhaps it was too hot at that point and even the fans on couldnt help. car has 130,XXX miles on it. i never replaced the water pump and im hoping thats not the problem. what do you guys think?

 

Jump the fan relay under the fuse box cover in the engine bay. If your main cooling fan kicks on, I'd suspect your thermostat is stuck closed, preventing the hot coolant from ever reaching the ECT sensor, which turns the fan on. When you're letting the car idle and overheat, have you ever touched the lower radiator hose to feel if its hot?

 

It sounds to me like you actually diagnosed your own problem when you stated that your radiator fans do not activate. Like saikou posted, I would check-out the electric fan relay. Also try checking the fan switch.

 

no i have not. but i just ran a lil test to see if its the lack of fans causing my problem. apparantly its not because, i started the car up and turned the AC on full blast which turned the fans on. after about 10 mins, it still overheated what should i try now?

 

Like I said, when it starts to overheat, reach down and touch that lower radiator hose. If its cold, replace your thermostat. And I'm not too familiar with the A/C fan as I've never had A/C since I've owned the car, but when you turn the A/C on, it kicks both fans on at the same time? I thought it only kicked the A/C fan on the right, as the main cooling fan is controlled by the ECT switch. I could be wrong.

Also, since our cars have a digital temp gauge, a loose ground can throw the gauge off and make it look like we're overheating. I just found that out when I replaced my Civic 1/2 radiator with a full size KOYO aluminum to see if that was the problem. Turned out, the little negative wire that runs off the negative post of the battery to the frame was loose. Tightened it down and fixed the problem.

 

damn i JUST had to replace my starter which involved taking the battery out etc. i thought i tightened that ground down but i definetely am gonna go check it right now. brb

 

ok so it definetely wasnt tightened ALL the way down but it doesnt matter as long as its making contact right? the car is idling now...waiting to see what it does

 

thermostat.

 

I do not have the OEM negative cable anymore, so my battery post is a little different. The small negative cable from the frame to my negative post is bolted onto an after market post clamp, which ended up coming loose due to vibration. But that is a start, definitely be sure everything is nice and tight.

 

how can i test the thermostat? the last time i ran the car idling in the driveway, it went up to redline and back down to 1 bar over thn back and forth a couple times without me changing anything. weird.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KB96VTEC &raquo;</TD></TR><TR><TD CLASS="quote">how can i test the thermostat? the last time i ran the car idling in the driveway, it went up to redline and back down to 1 bar over thn back and forth a couple times without me changing anything. weird.</TD></TR></TABLE>

Boil a container of water and place the thermostat inside of it... you should notice the spring mechanism in the thermostat begin to open the thermostat due to the intense temperature. Be sure that the thermostat is cool before doing this.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KB96VTEC &raquo;</TD></TR><TR><TD CLASS="quote">how can i test the thermostat? </TD></TR></TABLE>

some1 already told you

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by saikou &raquo;</TD></TR><TR><TD CLASS="quote">Like I said, when it starts to overheat, reach down and touch that lower radiator hose. If its cold, replace your thermostat. </TD></TR></TABLE>

Also check the grounds wires, especially the one that goes to the thermostat housing