Overheating only during stop-and-go traffic AND long freeway drives

[90gs]

I searched but couldn't find anything completely relevant to my problem so I hoped I could get some new insight.

My car (93 Integra) overheats (not fully, just to 50-60% of the gauge) on longer freeway drives and stop-and-go traffic after a while. Turning the heater on helps negate the problem but not fully.

Here's what I know:

-Water pump and thermostat were replaced ~20k miles ago
-Fluids are full
-Fans don't turn on (but that doesn't explain freeway overheating)
-When sitting in stop-and-go traffic I can rev the engine in neutral and the temp gauge will go back to normal

I'm about to go on a road trip in a few weeks so any and all help is greatly appreciated.

[jsurrett]

i have the same problem i would like to know also mine is a 1995

[warrenmoo]

Had that same problem. Did a compression test. Blown head gasket. Replaced and worked for 2 weeks and happened again. Head bolts were streached and contacted bottom of bolt hole. Replace head bolts (best) or use the best washers available.

[94tegRS]

whats the temp like outside? wheres your tach sitting at when you cruise? faster you drive, sure the more air that passes through the radiator, but the higher your engines revving creating more heat.

and in stop and go, not much air is passing the radiator if the fans dont turn on, so that could be both those problems. and 50-60% of the gauge really isnt overheating.

you could get a thermostat that opens at a lower temp.

but about the revving it in neutral, how long does it take to drop, because that makes no sense, you are getting the same amount of air, but creating more heat. try putting in in neutral and not revving it for the same time period and see what happens.

if it doesnt lower like it did when revving only thing that comes to mind is for some reason not enough coolant slow unless the pump is spun up alot faster?

after the pump/Tstat was replaced did you bleed the air out of the head. I dont remember exactly where it is but theres a bolt with a little nipple on it, and the way I always did it was put the hose to the radiator to pressurize it a bit, and with the engine running I would crack that bolt loose and wait until the water ran with no air coming out at all, then tighten it. but I ran all water, my buddy ran 50/50 so he did it by letting the car get warmed up and then cracking that bolt for a second to burp the system, just did that a few times until no air sputtered out with the water.

[somick]

Originally Posted by 94tegRS

you could get a thermostat that opens at a lower temp.

... or a bad thermostat.

Originally Posted by 94tegRS

after the pump/Tstat was replaced did you bleed the air out of the head. I dont remember exactly where it is but theres a bolt with a little nipple on it, and the way I always did it was put the hose to the radiator to pressurize it a bit, and with the engine running I would crack that bolt loose and wait until the water ran with no air coming out at all, then tighten it. but I ran all water, my buddy ran 50/50 so he did it by letting the car get warmed up and then cracking that bolt for a second to burp the system, just did that a few times until no air sputtered out with the water.

If you follow the lower radiator hose to the thermostat housing you will see the bleeder screw. It looks like a cone shaped screw. At least that is what I have on my Accord. I am pretty sure Integra has the same layout.
And there is no need to run your engine. Turn the bleeder half to one full turn. As soon as you see a steady stream of antifreeze coming out of the bleeder, top off the radiator and you will be fine. By the way it is 12 mm wrench you need for that screw.

Good luck,
Sam

[94tegRS]

on the B series though, its on the neck where the upper radiator hose goes into the head.

http://i77.photobucket.com/albums/j8...8/DSC00246.jpg

you can see it there.

also, I think that its high enough that if you open it without coolant pumping the air wont bleed out. not sure though, was told to have it running and I just did it that way every time.

and I thought about a bad tstat, but it just didnt make sense to me unless its fault it just opening at a warmer temp then when new, and now that I think about it maybe just not open as far, but when my trucks tstat stuck closed and I didnt catch the gauge in time I blew the headgasket.

[yangfue@gmail.com]

just custom a switch for the fan let the car cool down but i thinks it's your water pump

[jyount]

Originally Posted by yangfue@gmail.com

just custom a switch for the fan let the car cool down but i thinks it's your water pump

sounds like your radiator is clogged internally to me

[Shafto]

man sounds like this is common, cause I have the EXACT same problem, The first time it happend I also noticed that is directly RPM related. The faster my engine turned, the cooler it was. It was happiest bouncing off the limiter. This happened on up hills whare my rpms were lower and it was working harder. or at idle (lowest rpms).

I thought it was my water pump cuase of the symtopms, my fans did work I should say as well. so I did my water pump and nothing happend, then I just took out the thermostat (right out) and it ran cool as could be. so i knew my problem, I took a closer look at the thermostat and it was really sticking shut but still moved, so my theory is the more rpms, the more vacuum from the water pump, opening the thermo slightly allowing more coolant to flow.

Anyways, replaced my thermo, fixed the problem.