CruzR2011

Hi guys so ive read the FAQ and pretty much every thread listed fan not turning on, on 1992-2000 civic. And to no avail i can't seem to find the answer to my problem

Now here's my problem, the car doesn't over heat often only after a 100 mile+ trip. But when it does it blows hoses. Heres what i've already done and checked:

Ive replaced the sensor on the thermostat housing twice but haven't tried an OEM one of which i'm almost tempted to try here if something doesn't solve this.

I've checked relays, they're fine, when i bridge the sensor with a paper clip the fan turns on, so the fan works.

I've also checked the Black/yellow wire coming from the ignition switch, it checked out fine 11.75v. By now i've covered everything i've seen. As i type this i'm also bleeding the coolant just to cover that base.

All tips/help/comments are all appreciated. Lastly i don't want to wire a switch and i already know thats an option i might have to take.

Former User

Have you replaced the thermostat and bled the cooling system?

Have you tested for exhaust gas in the coolant using a block tester? White smoke in the exhaust? Bubbles in the coolant? Coolant in the oil; oil in the coolant?

Have you pressure tested the cooling system?

CruzR2011

I haven't tested exhaust gas in coolant, That's something i'm putting on my list now
No bubbles in the coolant.
there isn't white smoke coming out of the exhaust,
and i just got done bleeding the system,
Thermostat was replaced about a month and a half ago
and Neither oil in coolant or coolant in oil, i'm also not loosing coolant or oil to help cover that base. I check the coolant every couple days to try and get a clue but it stays up.
No i haven't pressure tested system either

I'll do both the exhaust gas and pressure test tomorrow hopefully (it's dark) and respond asap.

CruzR2011

Okay so sorry for the delay but had a friend at his shop test for exhaust gas and pressure test, both came back okay, i did for curiosity measures changes out the aftermarket coolant fan switch with an OEM one and still nothing, its just frustrating because the fan does turn on when i bridge the sensor.

CruzR2011

So randomly the fan turned on yesterday, i have no clue as to why but its the first time it turned on in about 4 months. So its fixed hopefully

HondaEm1-00

with your car off. spin your fan by hand. is there friction. it should not spin freely. if spin freely you have a short in fan clutch or a bad clutch. ever thought of disconecting your fan clutch wires and run to a manual switch in your car so you can control when comes on etc. does this help you at all on info im giving?

HondaEm1-00

just read you do not want to wire switch so possibly bad info apologies.

CruzR2011

it's fine, but its working now i think its just a delayed reaction of the bleed possibly? Because since the day i bled it i hadn't done anything to it.

CruzR2011

Okay so the fan hasn't been working again, now what happened the day it turned on i was putting seafoam through the vacuum line (picture pending), and it turned on. I just opened that vacuum line again and viola the fan turned on, does anyone know what this means? As long as the vacuum line is off the fan turns on.

CruzR2011

Its the vacuum line above the brake booster,

CruzR2011

Also the only CEL code it spits out is code 17 the VSS, which was rewired by previous owner, although the fan worked for the first year ive owned it.

CruzR2011

Okay so after a long hard fought day it started working again, i disconnected every plug in cleaned them all out, and sanded down all grounds and it started working again.