Hi everyone I am new to this forum and forums in general. I bought a 1992 civic Si last year and since then I have had to replace:

a busted radiator
water pump
thermostat- previous owner had voided car of the thermostat
radiator cap

to no avail my poor civic keeps sticking to the H on the temp gauge.
The hoses appear new and all I think could go wrong is a blockage of some sort in my coolant system. I was hoping someone on here may have had similar issues and could offer me insight. I love the car to much to give up and sell/junk.

 

have you bled the coolant system and are you lacking compression in any cylinders or are you burning coolant

 

since u said u replaced ur water pump...u might also need a head gasket..and might have to bleed the system also

 

I'm about to bleed the coolant system. I haven't had my compression tested but I don't see any signs (that I currently know of) that I need a new head gasket. Although that option is still open. I have found that the engine only cools down when I turn on the heater. I know that's a common trick for bringing engine temperature down but I don't even have to run the fan for it to work. It can go from red zone to half way on the temp gauge in a few seconds this way.

 

Does your radiator fan turn on when its supposed to?

 

Yea the rad fan cuts on at 3/4's on the temp gauge. The car likes to stay cool when idling but when I get up to highway speed or anything above 45mph (shifting below 3k) the temp starts to climb all the way up.

 

Pull your spark plugs and look at the top of the pistons. See if any look steam cleaned rather than black. Kinda sounds like a head gasket.

 

Also, bleeding.....Very important.

 

Excuse the obvious question, but are you sure it's overheating? And not a bad ECT sensor or sender, giving false information to the gauge cluster?

 

Thats a good question tlarimer......He says the radiator fan doesn't turn on until the gauge is 3/4 of the way up. It should be turning on under half way I believe....

 

My 92 EH3 the fans turns on just below half way mark and that's where my constant operating temp is as well

 

This is a dumb question where would the ect sender or sensor be located?

 

Original D16Z6? There are 2, one on the distributor side of the head and one on the back of the block. One sends signal to the ecu, the other sends signal to the gauge cluster, cant remember which is which, my d series go yanked out a few years back.

 

and are the etc and a coolant temperature sensor the same part?

 

No, they have different functions and are different P/N's.

 

ok I found both the sender and sensor. I forgot to mention that my check engine comes on every now and then. It's beginning to sound more like an electronic issue. Thank you all for the help!

 

Have you pulled the CEL?

 

pulled the CEL got six short flashes. I looked up that code and found it was the ECT. My fan stopped coming on at all. ECT sensor comes out next weekend and hopefully that's the last time I overheat for a long while

I parked the car and I hope I didn't blow the head gasket from that last drive out to town

 

the ECT code would only be for the sensor that provides the ecu with temp info. If the ect fan switch, or temp sender unit for the gauge cluster failed, it would not throw a code.

 

hi D16sihatch I just googled that fan switch and found a thread where you explained that the fan switch sits on the thermostat housing. Thank you! Do you think I should go ahead and buy a replacement ECT sensor because of the CEL code then test my fan? If the fan works when it's jumped can I be sure it is the ECT fan switch malfunctioning?

 

if the fan kicks on when jumped, then i would replace the switch. assuming in fact the engine is overheating and the gauge on the dash is reading correctly. i would test the fan switch to be sure

 

I took a paper clip and used electrical tape to permanently run the electric fan and even that isn't working. I admit that I rigged it this way after the engine had already been pretty hot. Should I wait for the fluid to cool (and check it of course) and try to see if the engine can hold a steady temperature after letting it warm up again (with the electric fan constantly on)? Or just assume it's the gauge giving me a bogus temp reading?

 

no smoky exhaust and no other signs of a blown head gasket except for the overheating. I will still check both coolant and oil for bubbles tomorrow.

 

What happened to checking this?

 

With all the cooling system problems you've had, has the engine severely overheated multiple times?