boost a pump failing?

[08redgt]

Hey guys! Took my car out tonight and it stalled on me again. Turned out to be fuel pump fuse again. Ran to auto zone and it ended up eating another 30amp fuse. Its running fine now but wtf is going on here?!? I didn't see any exposed wires and my bap is all hooked up

 

[michael.konor]

I'm going to assume that you're blowing the BAP fuse, and not the FDPM fuse.

Fuses blowing is caused by two things, a short or an overload. Which one you do first is up to you, but finding a short is easier than finding an overload.

Short: Check the *entire* length your wiring after the fuse for an intermittent short. I've found that you have to physically run your hand along the wire and feel for any cuts and chaffing damage. Pay attention to areas where parts of the car may come in special contact with the wire. Also look for any melted points, or bad wire junctions / connections while you're at it.

Overload: The overload is originating from either your BAP or from the fuel pump(s).

Questions First: Where do you have the dial set? If you turn it to the lowest voltage setting, does the fuse still blow? At what level of driving does the fuse blow?

If you remove the BAP from the circuit, does the FDPM fuse pop? If yes, look at fuel pump(s), as well as their connections.

If you remove the BAP from the circuit, does everything work fine (except for not having the BAP...)? If yes, look at the BAP.

To check the BAP you need a way to monitor current exceeding 30amps, or just remove it and send back to KB and have it checked.

 

[08redgt]

I'm going to assume that you're blowing the BAP fuse, and not the FDPM fuse.

Fuses blowing is caused by two things, a short or an overload. Which one you do first is up to you, but finding a short is easier than finding an overload.

Short: Check the *entire* length your wiring after the fuse for an intermittent short. I've found that you have to physically run your hand along the wire and feel for any cuts and chaffing damage. Pay attention to areas where parts of the car may come in special contact with the wire. Also look for any melted points, or bad wire junctions / connections while you're at it.

Overload: The overload is originating from either your BAP or from the fuel pump(s).

Questions First: Where do you have the dial set? If you turn it to the lowest voltage setting, does the fuse still blow? At what level of driving does the fuse blow?

If you remove the BAP from the circuit, does the FDPM fuse pop? If yes, look at fuel pump(s), as well as their connections.

If you remove the BAP from the circuit, does everything work fine (except for not having the BAP...)? If yes, look at the BAP.

To check the BAP you need a way to monitor current exceeding 30amps, or just remove it and send back to KB and have it checked.

It's the fuel pump fuse in the engine bay.

Thank you for the reply btw! First thing tomorrow I'll run along the wires and check for a short. I have set to tge richest setting per my tuner.

It did this about three months ago too but I haven't had any problems after replacing the fuse until now.

 

[JeremyH]

Couuld be an internal short in the bap as well not just external like mentioned. Time to upgrade

 

[08redgt]

Could an exposed wire going to tge bap cause the short if it touches the body of the car?? If so I found it. My wonderful wiring skills strike again lol. Drove it around the block a few times and it didn't die. It's bucking when I shift into 4th sometimes but I think that's cause it's still a draw through system with the front mount (parts go in tomorrow along with the retune)

 

[konablue11gt]

Could an exposed wire going to tge bap cause the short if it touches the body of the car?? If so I found it. My wonderful wiring skills strike again lol. Drove it around the block a few times and it didn't die. It's bucking when I shift into 4th sometimes but I think that's cause it's still a draw through system with the front mount (parts go in tomorrow along with the retune)

yeah i had this issue once .. Had a couple people in the back seat found when someone was sitting there it caused a short and blew the #13 fuse. shrink wrap is your friend

 

[BruceH]

If I understand correctly you are running the bap off of the stock fuel pump wiring? If so it's time to run a dedicated power wire to the bap and use the stock power wire to trigger a relay to connect the upgraded wire to the bap.

 

[08redgt]

If I understand correctly you are running the bap off of the stock fuel pump wiring? If so it's time to run a dedicated power wire to the bap and use the stock power wire to trigger a relay to connect the upgraded wire to the bap.

That's a great idea! Just run a larger wire straight from the battery? And have the stock power wire act as a trigger to the relay to power on the bap?

 

[BruceH]

That's a great idea! Just run a larger wire straight from the battery? And have the stock power wire act as a trigger to the relay to power on the bap?

Yes, that's it. You will gain headroom on the fuel system too. Jeremy has kits all ready to go.

You need a relay, socket, large gauge wire, (I used 8 but 10 will work fine) and a fuse to put as close to the battery or ebc as possible. Most people run a terminal off of the same stud as the battery connects to the electrical bussed center.

IIRC Justin at VMP gained 13% more fuel pump volume on a 4.6 3v just by upgrading the wire to 8 gauge. It was quite some time ago now but it's buried on his forum somewhere.

If you take your time this will still only take about an hour. You will need to remove the passenger tire and inner fenderwell. The rest of it runs under pull off trim pieces and the rear seat.

 

[JeremyH]

Could an exposed wire going to tge bap cause the short if it touches the body of the car?? If so I found it. My wonderful wiring skills strike again lol. Drove it around the block a few times and it didn't die. It's bucking when I shift into 4th sometimes but I think that's cause it's still a draw through system with the front mount (parts go in tomorrow along with the retune)

Yes a power wiring comin in contact with the frame will definetly do it.