92 Teg stock B18. When sitting in traffic sometimes it will start to overheat. Once the needle crosses half way on the temp gauge it goes up pretty quick. Once I start moving at 5 Mph it drops back to normal instantly. Both AC fan and Radiator fan are working and coolant level is good. What could be the problem? This only happens every once in a while and seems mostly after a long drive on the freeway (45 min).
Any ideas? I’ve been shutting the car off when the temp starts to climb at stop lights to keep it from pegging just really annoying and inconvient
If you aren’t visibly leaking coolant and you’re sure the fan/temp switch are working, id think either a blockage (unlikely) or the pump is going out. I’m assuming you have bled the system of air?
Stuck thermostat maybe. When you open the rad cap, how does the rad and coolant look inside? Any scale or rust? Have you had any service done with the cooling system prior to this? As mentioned, could be an airlock
No service done to cooling system anytime recent (within the past year). I was thinking possibly water pump. I’ll get back to you with how the coolant looks.
Well, first thing I’d do is pressure test the system. If it holds pressure, check that the rad cap is operating correctly and allowing coolant in and out of the overflow tank. If that seems to be working properly, I’d change the thermostat. It’s cheap and easy. Make sure to go oem on that. And bleed the system correctly afterwards.
That’s the order I’d do it in
It wouldn’t make sense to be the thermostat would it since it doesn’t over heat any time other than traffic. If anything it would be stuck open and not cause the problem. Whats the easier way to check pressure in the system?
As mentioned, are you positive the fan is kicking in? You actually saw it?
You should be able to rent a pressure tester. Pump it up to 15psi and let it sit. Watch the needle on the gauge. If it drops at all, you have a leak, either internally or externally. Or you can get a shop to do it. They wouldn’t charge much just for that.
It is still possible it could be the t stat still. It could be stuck part way or only opening part way
FYI, It is hot as HELL in the south right now. Even mine was overheating a bit while sitting in traffic! Not a bad idea to service the system any way. In the summer months I take my thermostat out, but didn’t do that this year! My DA is running with a Mishimoto 4 core Civic half radiator (it’s boosted), and my DB is running an EBay special racing radiator! Both are heating up a bit higher than normal this year! I am not saying don’t check it out, but how dose it run later in the day when it starts to cool off. Go start the car up at 7 in the afternoon let it idle and watch the temp. See if it gets hot, and there is your answer. If it stay cool, It is just hot as hell out side when you are stuck in traffic. Stay back a little from the car in front of you, so your car can get a little fresh air. Upgrade you cooling system with hi-flow fans, better hoses, and if in the bidget preformance radiator. Redline water wetter helps my turbo DA, I use it in all my cars.
I was thinking it was an outside temperature thing. I will do some playing around with it when I get a chance unfortunately school just started back up so I’m swamped already.
After a long drive (80 miles or so) the car would overheat at a stop light but the second I start moving forward temp drops to normal. This has happened 2-3 times.
Today I was driving down the road with no one around and the temp shot up to 3/4-7/8 the normal range of the gauge and then after about 30 seconds-1 min the temp dropped to normal.
I have this same exact problem and have been driving my teg like this for 2 years. It only does it when I’m in very heavy traffic like a stand still. I travel and work at night so it doesnt really affect me. For me its because my fans dont come on but ive diagnosed it and jumped my fans and they come one so I think its the fan wiring.
Both my fans are operating at least with AC on which I drive with it on all the time. I’m leaning to water pump or thermostat but thermostat doesn’t make sense to me.
Make sure all the fins on your radiator aren’t all smashed down and flat. I replaced like everything in my cooling system before realizing that I had so many smashed fins that it couldn’t breathe…Could be why it cools down once you start moving and air starts hitting the front of it again.
im having the same problem right now… and it sucks! ill be driving around town and my car over heats sooo quick… i try to turn the ac on so that the fans will come on… not the fans wont come on… my cooling fans come on but only when the needle is about to hit red zone… i try to use my windshield defroster to bring in hot air… but no hot air comes in… just cool air… any suggestions??
sounds like the switch on the thermostat housing (switch that turns the fans on) is becoming a dead component or has so gunk/rust on it that it’s not working properly. I say take the thermostat out and replace along with the switch. see if it changes the situation.