How to Direct Wire a Fuel Pump: A Step-by-Step Guide
If you want to improve the fuel economy and performance of your vehicle, you might want to consider running your fuel pump directly to the battery. Doing so will bypass the fuel pump relay and send more volts directly to your fuel pump, resulting in better pressure and more consistent flow of gasoline to your engine.
Why Direct Wiring a Fuel Pump Is a Good Idea
If you’re not familiar with how your fuel pump works, you might be wondering why running it directly to the battery is a good idea. Here are a few reasons:
- Improved fuel economy
- Better engine performance
- More consistent fuel flow
- Reduces power fluctuations
- No need to worry about the fuel pump relay
What You’ll Need
Before you start working on your fuel pump, make sure you have the following items:
- A compatible fuel pump
- A 12-volt battery
- A fuel pump relay
- A soldering iron
- Wire cutters/strippers
- Fuse holder
- A multimeter (optional)
Step-by-Step Guide
Now that you have everything you need, follow these steps to direct wire your fuel pump:
Step 1: Wiring in the Fuse
The first thing you need to do is connect the first wire to the positive terminal on the battery and attach the fuse. Here’s how:
- Cut a short piece of wire and clip one end to the positive terminal on the battery.
- Solder the other end to your fuse holder.
- Insert the 30amp fuse into the fuse holder.
Step 2: Connecting the Battery to the Fuel Relay
Once the fuse holder is in place, you’ll need to solder a longer cable onto the end of it. This cable will run all the way to your fuel pump relay and connect to terminal 30:
- Solder a longer wire to the end of the fuse holder.
- Connect the wire to terminal 30 on the fuel relay.
Step 3: Grounding
Next, you’ll need to attach the ground wire to terminal 30 on the fuel relay and the other end to a screw around the fuel pump area:
- Attach the ground wire to terminal 30 on the fuel relay.
- Connect the other end of the ground wire to a screw around the fuel pump area.
Step 4: Cut the Wires from the Fuel Pump
You’ll need to cut the wiring harness into two pieces:
- Cut the single wiring harness into two pieces.
Step 5: Attach Trigger Wire to Fuel Pump
Here’s how to attach the trigger cable (black and white with blue stripes) from the fuel pump to terminal 86 on the fuel pump relay:
- Attach the trigger cable to terminal 86 on the fuel pump relay.
Step 6: Attach Power Wire to Fuel Pump
Solder the power wire to the fuel pump (second wire that was cut) and connect it to terminal 87:
- Solder the power wire to the fuel pump.
- Connect the power wire to terminal 87 on the fuel pump relay.
Step 7: Put the Fuse in and Test
Insert the fuse into the holder and test your fuel pump:
- Insert the fuse into the holder.
- Test the fuel pump.
FAQs
1. Can I direct wire any fuel pump?
No, not all fuel pumps can be direct wired to the battery. Make sure your fuel pump is compatible before attempting to direct wire it.
2. What happens if I don’t attach the ground wire properly?
If the ground wire is not attached properly, you may experience power fluctuations which could negatively affect your fuel pump’s performance.
3. Can I run a switch between the fuel pump and the battery?
Yes, you can, but you should only do this if you’re experienced in working with automotive electrical systems.
4. How do I know if my fuel pump needs to be direct wired?
If you’ve tuned your vehicle and are experiencing power fluctuations or inconsistent fuel flow, you may benefit from direct wiring your fuel pump.
5. Can I direct wire my fuel pump myself?
Yes, but if you’re not experienced in automotive electrical systems, it’s best to have a professional handle the installation.
Conclusion
Direct wiring your fuel pump can be a great way to improve your vehicle’s fuel economy and performance. While it may seem intimidating, it can be done with a few simple tools and a little bit of know-how. Make sure to follow our step-by-step guide carefully and always test your fuel pump before hitting the road!
