I have researched all the fan tips, but can not find an answer to my question. I live in Florida, and have a 94 with a factory fan switch sending unit mounted between plugs 6 and 8 behind the oil dip stick. However, according to the instructions for my new fan switch, should not be on this car. The instructions say my fans are controlled by the ECM/PCM, however I already have a switch that appears to be original, and it cuts the primary fan on at 238 degrees. The plug on that switch only has one wire going into a wiring harness. I purchased a 185 degree from Ecklers, part # 40415 and it has two leads, a blue and green. The instructions say to run these wires directly to the fan relays mounted on the radiator. It says to connect one wire for a single fan turn on at 185 or connect the other wire to the auxiliary fan for both fans. Does this mean it will cut both fans on at the same time, and is it necessary to cut both on at the same time? If I only wire one, with the auxiliary fan still cut on with the A/C or when it gets to 235 degrees? When I leave the original wire disconnected, what effect will that have on the fans, and will it send any kind of false codes? Also, the directions say that the F terminal on the relay is the signal wire, but it appears that my F terminal on the relays does not have a wire connected. Does anyone know what color wire the main fan and the auxiliary fan should have? Lots of questions, but I appreciate the help.

 

Go to the tech tips section on the main forum page under the tools heading cilck and then and click on C4 tech tips. You will find directions on how to hook up your manual.switch a ways down the list.. There is no current running to these wires. Your switch merely grounds the fan relay which turns either one fan or both on dpending on which way you throw the switch. There is a hole behind the battery where you can run the wires. Remove battery and tape your wires onto a coathanger and push it thru the bunghole. it will come out above the clutch pedal. Mount the switch under the knee bolster area below thw steering wheel. it is made of cardboard and trim material. Ground the switch with the third wire using the screw and hole from the under dash cover. The two colored swtich wires get spliced into the same colored wires on the fan relays mounted on the left side of the radiator.


[Modified by jiml94, 9:10 PM 10/2/2003]


[Modified by jiml94, 9:15 PM 10/2/2003]

 

I don’t have a manual switch, it is an automatic switch. It is designed to cut the fan, or fans, on at approximately 185 degrees. Thanks for the tip on the wires.

 

I have a '94 also and sent for the same Ecklers switch. I agree their instructions don't seem to fit the scenario and the switch you mentioned between #6 & #8 cyl. is a fan switch on my '84 (older models). I don't know what it does on the newer LT1s. After looking over how much butchering of the wiring system is required, and that crappy wire splice/connector included I decided there's got to be a better way. Return that garbage back to Ecklers and reprogram the ECM to turn the fans on at the temp. you select. There's a few ECM reprogrammers on the market, but I haven't got around to it yet as the programmers cost a bit. You may want to check the space between your radiator and AC condensor for debris. Any accumulation there will block air flow to your radiator and cause the temp. to be high.

 

The only programmer I am aware of is the Hypertech Power Programmer III. Are there others on the market, and if so, do you know the name, and where they can be purchased? I did not consider the Hypertech because most of the reviews I have read in the Forum say they would not help my performance, and the only gain would be to be able to adjust my fan turn on point. I have a 6 speed, with a K&N open face, and adjustable fuel pressure regulator.

 

I also tried to go with the fan switch on my '94, but the temperature switch was in there soooooo tight that I gave up trying to get it out. I was also concerned about cutting into the wires, so I used a hypertech PP3 and reprogrammed the fans via the ECM.

 

About two years ago, I bought the switch from MAD and their instructions were wrong. I managed to change that switch between plugs 6 and 8 with the new one and it did turn the fans on early (mine was at 200 degrees). Problem was, the guage in the car would never come off zero until the fans turned on and then the needle on the guage would shoot up to 200 instantly. I got on the forum and someone clued me in that the instructions were wrong, the new switch actually should be put into one of the freeze plugs on the drivers side, up front (between 1 and 3?). I could not get the freeze plug out, so I took it to a shop and he got it out and installed the new switch. Wired it up, made it look like a professional job (with the black tubing :smash: ) and it works great now.


[Modified by 94Controller, 11:00 AM 10/3/2003]

 

Thanks for the info. Just to make sure I understand you correctly, I need to leave the factory switch in between 6 and 8 and also install the new switch between 1 and 3 where the plug is located. I know how to wire directly to the relays, but do I also leave the old switch that is between 6 and 8 connected, or did you unplug it when you installed the new switch?

Thanks again for the help.

 

:iagree: The biggest problem is trash pilling up in the radiator fins. When It removed my radiator on my 94 to clean out the fins, I looked like a cow had taken a crap right in front of where the primary fan sits. Immediately saw a 30 degree drop in temp (this was in the middle of summer in TX, and sitting in trafic with the A/C running, won't get above 225). NO PARTS NEEDED! Just clean it up.


[Modified by greggo's 94LT1, 6:16 PM 10/3/2003]

 

I agree, that is a problem, however mine is clean. My temperature runs with factory specs, I just want it to run a litter cooler. It gets awfully hot in Florida.