Have a JET fan switch and want to reduce fan turn temp......

Went to remove the original (maybe) fan switch and I find that there is a plug in the position that I believe is the right place..between #6 and #8 spark plug hole. There is a senser( Switch) down below the starter, just on top of the oil pan (where the pan meets the block). It has a blue wire to it. Looks more like a pressure switch. How do I tell if this is it, short of removal. Is this the knock sensor??? Tried grounding the wire with the Ign switch on..nothing. Need help..............

 

The one by the pan is the knock sensor, where you described the plug between 6-8 thats the one you want to replace or tie into however this jett setup installs but thats the one.



SSC

 

Ok.....i'm good with that, but where is the REAL fan switch????????

 

Unless they did something funny in '86, and I wouldn't doubt it, that plug between 6/8 is where it should be. You need to look around your engine bay and find the wire that once went to the sensor that is no longer there. Should be a single wire loose in that area. Look for something melted to your header

 

rezinn..thanks for the reply,

What color is the wire that is supposed to go to the fan switch???

By the way if the wire was not connected or burnt as you suggest, wouldn't the fan be inoperable????????

 

Usually it's a Green wire, coming from the Fan Relay. I wonder if that switch could be mounted somewhere on the intake manifold, instead of the normal location?

 

Thanks Changa2.... Can't find anything on the manifold that looks like a temp sensor, other that the ones that belong there.

You say the wire is green, is that wht/grn or plain green. Someone has just told me the wire is drk blu. Guess I'll just keep looking. Actualy I'm glad the fan switch was not in the right place, looks like a pain to get to it.....

 

It's in the head, not the block, between the #6 & #8 spark plugs. Should have a dark green wire.

 

My car is an 87 Camaro SC that was originally an LG4 (Carb) and the color is 'Green'. The wiring diagram that I have is for an 85, I believe, and they refer to it as 'Lt. Green'.

You ask about 'Wht/Green'. In reading many similar threads, in the past, and if memory serves me correctly, I believe that I have seen a reference to a 'Green/Wht Stripe'. So, just perhaps, some years did have the stripe.

Have you found your 'Fan Relay'?

My Relay (5 Blade) had four wires:

A. Black/Red St
B. Green (Coolant Temp Switch or Fan Switch)
C. Brown/Wht St (Bulkhead G7)
D. Blank
E. Red (Hot at all times).

 

I had a wire that was off at fan switchand fan still worked but it will only come on at approx 223 degs set by computer. I installed a switch from hyper tech, on at 175 0f at 165 and and installed a 160deg stat. It works great but fan pretty much stays on after initial warm up. The engine will last alot longer running cooler! Underhood temp is alot cooler too. This may explain why the injectors went bad in 60,000 miles with all the extra heat . 5 were at 3 to 6 ohms when they were suppose to be 14 to 16. Talk about running bad!!Now in 95 deg weather it does'nt get past 180 .

 

Changa2...Yeah I've got the relay....got all the colors...still can not find the swich........Thanks to all...but still can not find the switch

 

six8bird.....not sure what you are talking about...got 170* Termo..can't find the original, stock, fan switch location...injectors are great...........got a Jet switch..went to intall it..got a plug in the place of the (stock) location, between #6ands#8 spark plug hole...where to now.....I-4 interstate works great...in town..still get up to 220*......want to intsall the low temp switch, but want the right location....what is the wire color and any sugfgestions as to NEW location......

 

Ebby53... I have an '86 Trans Am also and my fan switch wasn't located where it's supposed to be either. It's "supposed" to be in the passenger side head between the #6 and #8 plug as mentioned earlier. When I took my 305 out there was no sensor there, only a plug. I have no clue why it's not there or where it was stock but my upper radiator hose is split right by the radiator and there's a 3 inch long piece of pipe there with what appears to be a fan switch welded into it and two red wires coming off of it and going into a wire loom.

I just bought an adjustable fan switch with a temperature probe that attaches to the radiator from AutoZone for $25 and wired my fan into that. I've had that setup for almost 3 years now and it works great because I can adjust when the fan comes on and goes off in case I decide to use a hotter thermostat in the winter so I have a heater and a cooler thermostat in the summer so the car cools better.

 

Thanks 86tTPI Trans Am..........What is the part no.? Got no switch where you indicated.... sounds like just what I want....but where to start?......I need a place to begin and cannot find it..You are just the guy that I need for other questions. My signature has my petigree..........Need help

 

Follow the Drk Grn/White stripe wire leading from your fan... It might just end up on one of the metal lines by the A/C. GM does some strange stuff. That was where I found the hookup on mine.
(Passenger side) Very strange.

 

I'll try to remember to call Autozone tomorrow for a part #.

It's really quite simple to hook up and comes with everything you need including electrical connectors and wire. It has two terminals on it. 1 terminal goes to the battery and the other terminal goes to the hot wire on the fan. The fan has only two wires, one is a ground and the other is power. Figure out which one is the power and cut it, then wire it to this thermostat. The instructions are very detailed. After you have it wired up there's a metal thermostat probe on it that extends out and attaches to the radiator with use of the included hardware. The adjustable unit itself is small and can be mounted anywhere ... I mounted mine on the drivers side near the firewall where all the other relays are. Start the car and once the temp reaches your desired temp where you want the fan to come on, go up front and turn the **** on the switch just until the fan comes on and you're all set. You'll never have to adjust it again unless you want. Once the temp probe reads lower temp, the fan shuts off and the when it reaches the desired "on" temp it comes on again. It's all automatic yet adjustable so you have some control over it as well.