Like many of you I am sick and tired of pinging. Most of us know that alot of that has to do with heat soak under the hood.

I am going through the process of doing a few mods to help with the pinging.

First one is Fan control.

The mod is very simple. The ecu sends a ground to the fans high and low speed relays. All we are doing is applying a ground to the high speed relay when we want. Either all the time or as desired via a switch.

I have this mod on my turbo charged sentra. It greatly helps with heat soak on the hot florida days.

Some of the benefits of this mod are, constant airflow through the engine bay. It will prevent stagnant air from heat soaking the motor. Since Both fans will be running on full all the time, It brings more air across the a/c evap. That will keep the a/c running more efficient and cooler. It will also keep the air cooler while sitting at lights.

This mod is pretty much fail safe. Since the wires are still connected like factory. If the ground disconnects or the switch fails the fans will still be controlled by the ecu.

1. Unplug the battery

2. Locate the fan relay box. Its on the drivers side. On the top it labels the relays.

3. unbolt it, flip it over and remove the white plastic bottom. Its attached with plastic tabs that can be gently pryed open.

4. Locate fan relay 2 and 3 by using the relay box lid.

5. Locate the light green wires on both relays

6. You can either cut, join, and add a lead the wires or tap these wires

I choose to cut and add a lead. The reason I do it this way is because the factory wire is very thin and splicing and tapping each wire individually can be risky. Joining the wires and adding a thicker lead is stronger.


7. Tap the wire(s)


8. Here is where you have an option. You can run a wire to the negitive terminal of the battery or ground it to a bolt on the frame. This will keep the fans on all the time


You can also run a wire to a switch and connect the other end of the switch to a ground. This method will allow you control the fans by the ecu. Just like stock. Or you can turn the fan on and off at will by using the switch.

Using a switch is more beneficial in colder climates where proper warm up is required.

 

Correct me if I'm wrong, but can't you get a temp switch that will operate the fans at lower engine temps?

 

I am sure something like that exists.

Theres other things as well such as lower temp thermostats, distilled water.

This mod is just a quick no cost/low cost improvement

 

Since the factory fans operate at low and high speed, what speed will they spin if you hook them up like this? Basically what I am trying to ask are you fans spinning all the time now on the low speed or the high speed?

The low speed fans come on at 203 degrees Fahrenheit and the High Speed come on at 213 degres Fahrenheit.

I actually have bough a fan switch kit that is adjustable and have my fans set to come on at 180 degrees Fahrenheit.

 

You have options with this. If you do the light green like the how to shows, you will have high speed. IIRC the blue/red wires are low speed. So if you ground those it will be low speed all the time. You should be able to combo the connections. Like low speed all the time with high speed on a switch

 

It is not a bad idea since constant now there is constant airflow. However having the fans running all the time especially at high speed can get annoying since they are loud.

A better option is an adjustable fan control kit ( single or dual ) and then you can adjust the temp from 160 degrees to 220 degrees. They can be found for $30 and up depending on the style.

 

True but they can only be heard outside of the car. even with the windows down at a stop light you cant hear it

 

So did this help with the pinging? You're talking about the 1700-2000 pinging under light load right?