[Ashby]

Ok so at 70mph with the A/C on, myu car starts running hot. If you turn the A/C off, it will start to cool off.. This is only at 70mph.. The temp fluctuates with the RPMs sometimes. If I clutch it and let the car go to idle, it will cool off.

I can drive all day long doing 55 and it will not run over normal.

Any ideas?

Waterpump works
Both fans work correctly
New temp sensor
New thermostat (working)


Could it be possible that the radiator is messed up? My stock radiator has a smaller top outlet than what is on the engine.. Could that be a problem?

This is on a 90 Civic Wagon (same as ef) with B16a swap.

 

[Ashby]

well with the fact that your going 70mph that means your rpm are kinda up there.
and the fans dont do that much at those speeds.
the problem alot of times is the air dam under your car like a little black plastic peice hanging down.
its job is to push air up to your eninge. so if you lowered your car and broke it off or took it off that would be ot.



or one of your hoses are clogged a little....but not too much to matter at lower speeds.

Guess it could be cause I never installed the air dams back into my car when I swapped the motor.. I think I'll put those back on and see if it helps any..

 

[Ashby]

Yeah that is what I was thinking of as well.. I put the air dam plastic stuff back on so we will see if that helps.

I was going to pick up a Cometic head gasket the other day.. But I decided not to.. We will see..

 

[Ashby]

Installed the air dams and it still is doing it.. Any ideas? I'm thinking radiator..

 

[Ashby]

Well If I am going 70 and it starts warming up if I clutch it, it will cool down, then shoot back up really fast... If I turn the A/C off it cools off. If I go under 70 it will never do it..

I think the radiator isn't letting air flow correctly, causing it to warm up..


BUTTTTTTTT

When it warms up and cools down it jumps fast.. Doesn't slowly do it, it goes fast.. Possible temp sensor?