Ok guys, just got finished with a high compression build, when I turn the key over, the fuel pump primes up half ass and blows the 30amp engine fuse. The wiring was never touched during the build so Im really stumped as to why it would be shorted or anything. I replaced both MFI and ASD relays just to be sure, and nothing has changed. Thanks in advance for any helpful info


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Mine was doing that on my turbo build. I was using the walbro 255 and the fuse kept popping. I stuck a 40A in there and haven't had a problem out of it. Later I found out that the pump was shorting out in the tank, fixed that and never had another problem with it. Make sure there is no possible way for any of the wires going to the fuel pump to touch anything. If there are any breaks, fix them. If you upgraded the pump, I'd recommend the walbro wire mod. I think there's a write up on it.

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ah... turbo. I love the turbo, the boost, the speed, the sound.
and its all better when you do it yourself. cheaper too.

I am currently running a wally 255, would it matter if I am still using it even though I'm back to all motor? I put the 255 on just because I was boosted. Should I take it back off and go with a smaller pump? I also tried putting a 50amp fuse in yesterday and the pump acted like it was going to prime up, but before it finished the fuse had already blown. I will go through the wiring again today just to triple check everything

running the 255 while NA shouldn't be a problem as long as you have a proper FPR to control the flow. lots of guys run the 255 while getting ready to build for a turbo.

Erik P.
Official 2GNT thread Hijacker
Some say that he's driven over more Covenant than he's shot, and that his grenades aren't where you'd expect them to be...
All we know is, He's not The Stig... But he is The Stig's Spartan cousin!

How long was the car down for the rebuild? How much fuel in the tank?

Could be that, because God hates you, the fuel level was low enough and the fuel broke down enough that your first tries at starting it up are pulling a bunch of sediment into the pre-filter, jamming up the Wally, resulting in a higher current draw, which is popping fuses.

Before you go cutting wires and shit, can't hurt to pull the in-tank for inspection. I recently had a similar problem on a Galant VR4. Wally was jammed up (beyond repair) and the 30A in-line on the re-wire was popping as soon as I energized the circuit. Replaced the Wally and all was well, although I had to then replace the pre-filter twice before we got all the sediment out of the tank.

Car was down for about 2 months with about a quarter tank of premium unleaded and at least a couple of ounces of Lucas octane booster. I will pull the pump today to check, and I was also wondering if there is any way I could have purchased the wrong fuel pump relay? The numbers on the relays are the exact same and of course the prongs match up. The only thing I was worried about is that the new relays I purchased don't have a metal piece that bolts up to the firewall. Does mounting the relays to metal provide a ground that I'm missing? I hear the "click" when the key is in the "on" position. Is it possible that the new relay isn't providing the proper resistance? Thanks for the help