Cooling fan woes.

ASSISTANCE Stock Engine-Bay Components
1

Just a quick question concerning the fan switch and/or cooling system… But first, a slight background.

Before I completed my motor swap, my Integra was sitting for nearly 3 years.

Since my swap has been finished and I’ve been doing the break-in period, the cooling fan(s) have never come on… Yet the temp gauge always has been steady at operating temperature, sitting just shy of the half-way mark on the gauge. Even during the summer when driving it, never once did it get hot.

I figured it was just coincidence that I never saw the fans on, and left it at that.

A few weeks ago when on the dyno, after about three pulls, it got hot… Above half way. Naturally, we threw the big floor-fan in front of it and it fell right down to operating temperature.

The next day I disconnected the harness from the thermostat housing fan switch, and jumped the plug with a piece of wire… The fan instantly kicked on.

I’ve since gotten a BuddyClub fan switch, but since the car is in storage I’ve yet to replace it.

On to the main questions…

  1. By jumping the harness connector, this is simulating the fan switch “closing” the circuit, correct? So I am safe to assume that all the fan relays etc are functioning correctly?

  2. when doing the swap I removed the A/C system, pump, condenser, etc… Would have that have any affect on how the fan switch and cooling fan will operate?

I realise I could look this up in the wiring schematic… but for one I’m actually out of town at the moment, and two, I’m an idiot when it comes to electrical and wiring.

Bottom line, I have the new fan switch that I’m hoping will solve my cooling fan issue… Is there anything else I should be looking at as far as the culprit?

The car is an OBD1 1993 LS… running on a chipped/tuned P28 ecu.

Thanks for any help you folks can offer!

2

well it sounds like you have it pretty well narrowed down…

what about the ECT sensor? seems when I had cooling issues while replacing my entire cooling system Welfare had me check both the fan switch at the radiator and ECT sensor at the back of the block…

as far as condenser (AC fan) and the cooling fan they both operate simultaneously regardless of AC being there or not. When I first got my 91 GS I had no cooling fan, just the condenser fan & it operated in place of the cooling fan. MY AC is dead so I never turn it on. my dummy understanding of how AC & condenser work is that the condenser fan can be actuated independently when the AC pump clutch engages or simultaneously with the cooling fan when it is actuated.

Later after installing slim fans on both sides they worked together in conjunction with the cooling system & condenser operates independent of AC system with the cooling system I.E. they both kick on and off at the same time when the cooling circuit is actuated by the fan switch & kick off when the engine reads that it is cool enough to halt operation.

hope that helps a little…

3

  1. Yes jumping the fan switch plug simulates, what the ECT switch does, [it “closes” at about 198 degrees F] and yes the rad fan, rad fan relay and wiring is good.

  2. Removing the cars A/C system will have no effect on the engines cooling system. 94

4

Thank you both!

I’ll look into how to test the ECT Sensor and do so when I replace the ECT/Fan Switch.

5

hey least I can do considering all the wisom I have gotten from you bud :slight_smile: