I have a weird overheating issue.. I have a full list of mods to my motor but in the short, its a built b18c1 with a precision 6262 and an AEM EMS. If any other mods are needed to help let me know. The issue im having is every once in a while a little while after starting and while driving, the motor will start to overheat, the computer realizes and it cuts power to the motor. Shortly after it cuts power, while still coasting, the temp drops back down and it functions fine after. It only happens the one time shortly after starting and driving and then is fine. fan turns on fine and after it happens, I can sit and idle for however long. Not sure what is going on. was thinking maybe the thermostat was sticking interm. maybe? only has a little more than 3000k miles on it but I know sometimes theyre bad out of the box. Any thoughts?

 

Swap out the thermostat, they are cheap enough to eliminate that as the problem.

Question, does the rad fan turn on as it is overheating, or only after temp. drops? 94

 

My guess is that only one fan is turning on.

 

Hard to tell if fan is turning on because im driving and can tell. Afraid to stop and check because of lack of air flow... Thinking ill start with the thermostat...

 

If the thermostat was bad it would overheat all the time. Idle the car and wait for the fans to turn on while watching the temp gauge.

 

Not necessarily, it could be "sticky" and intermittently stick closed, it's a cheap easy fix if that is what is wrong, 94

 

Thermostats either work or they don't. There is no in between with them.

 

This is the part you're looking to replace,
It runs out every 10-12- years or so
​19301-p08-315
Or -316
Thermostat Assy.
E-15-1 Water pump/sensor (dohc) ??? Honda ????? ??????? 1999 ???? 5MT - ????????
All B18C have the same.
As well Honda parts now displayed it for CRV b20. Probably Because I previously searched parts for.

This is the part everyone underestimate in build, and it does exactly that, intermittent overheat. Vent is not switching, because sensor is on the radiator. When Thermostat (heat sensible gas valve) not working is not opening cooling to run thru radiator, so on engine runs as on warming mode and at a point overheats. Ecu cut of for good.
Up to you boil the engine or not.

Beware there a different temp sensitive aftermarket Thermostats .
My guess is low temp opening one for over revs or boost, OEM for standard N/A
Cheers

 

20USD OEM,
You need to drain all cooling liquid, and save to fill engine back. Otherwise you face another $$ replace it. Edit on previous post. There thermal sensors switch for the fan is on the exit from engine hose to radiator pipe, there is another 2 on the inlet hose. Up to schematics is which one starts the fan. But let's save it for separate thread.

 

Helped me allo thanks