Weird Overheating Situation

[Catspa]

Any help on the following problem would be greatly appreciated
I’ve got a 94 Civic LX Sedan. The other day I was accelerating from light, and my car seemed to start chugging/hesitating, so I looked down at the garages and my temperature age was substantially above normal (was at ¾ mark) now it wasn’t in the red but it was close. So I immediately turned off the AC, and coasted for about 3 second with my foot off the gas, during wich time the temperature came write back down to normal. Ya within three seconds, it went right back to normal. So I turn on the AC and continue driving, watching the temp all the time, and it seemed fine, but every now and then it would suddenly clime, and suddenly come back down. So I didn’t know what to make of it. Soooo I stop in a parking lot and sit there idling, watching the temp guage all along, and sure enough as I watch the temperature guage starts to rise slowly, it gets to about ¾ of the way up, then stays there. I then give it some gass, (rev it high) and the temperature goes back down.. then I let it idle, and it goes back up, rev the engine and it goes back down (and goes down quick)…whats up with that?????? Rev the engine and engine temp goes down?? (and yes the coolant fan is going the whole time). Any ideas? Since then its only does it now and then.

- no signs of oil or anything in the coolant, (doesn’t look like a head gasket problem at least I hope not)
- Coolant fan is running
- Rad hose is hot.

so anyone have any ideas? What would cause the temp to go down if I rev the engine.

Again any help appreciated, thx!

[Duatone]

most cars can, and will, overheat/raise in in temp when they are in the idle position, but thats due to a bad fan or something, but anyways, try flushing out your radiator and the entire coolent system, either you can do it or take it in, shouldnt be much for a coolent flush. this might not be the fix, but its something to try. I had to do this when my car kept raising in temp, and now it works like brand new, you might also check the thermostat

[Catspa]

Ok thanks for the advise. The thermostat seems to be good, but flushing the system seems like a good start.
Still find it strange that the temperature would go Down when i revd the engine, it just doesn't make sense....

[95cvccvx]

sometimes the thermostat looks good but it could be messed up. Not being able to open and close. Like Duatone said try flushing out the radiator and motor. Also buy a new thermostat its less than 8 bucks nothing to lose if thats not the problem. Thermostat comes in different temperature ranges like 160 180 190 or something like that get the coolest stat. all yeah make sure fan is working.

[Catspa]

Ok, sounds good... bytheway - it hasn't done it since.. go figure, but i'm going to flush and look at puting a new thermostat in.
p.s. I read somewhere recently that geting a cool thermostate or performance thermostat is NOT a good idea, what ever i was reading basically said it could end up damaging the engine... can't remember why, other then i told my self after reading the info not to buy one... had something to do with the engine being designed to run within a rather small optimal temperature range...
:bandit:

[95cvccvx]

catspa that sounds about right, running a cooler thermostat is bad for the car. The car will run extremly rich the motor will shake and vibrate not healty for engine. The right time to run a cooler stat is when the engine running extreme heat like turbo,supercharger,nos. Use a thermostat thats recommanded for the manufacture. Also, if your car is having a hard time passing smog cuz its running too rich(cold) try running the hottest stat u can find for your car and then replacing it back.

[Catspa]

Hey, thats pritty slick advice, wish i new that with my last car, could have saved me some $.
Thanks again.