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Discussion Starter · #1 ·
For some reason I keep blowing the efi 30amp fuse.....the car is a 98 sc300,soarer 1jz/r154 swap,single turbo, 550 mk4 injectors with a resistor from a Acura TL installed a few months ago and never had any isues.The other day I was cruising at 40mph and the car shut off,no sound from the fuel pump.I fine the efi fuse blown,I go ahead and replace the 30amp fuse,it blows again as soon as I turn the key to ACC.


I have tried different steps to pin point the problem...but no luck

-I disconnected the resistor to check if it is causing the issue,fuse pops again as soon as I turn the keep.

-Disconnected all injector plugs,it pops agin once the key turn

-Disconnected the ecu....fuse pops again


If anyone can help me out please give me some info as to what maybe causing this random problem
 

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My alternator wiring wearing through caused this to happen on mine. Exact same chain of problems. Worth a look. Mine was arc-ing against the block. . . Took me ages to find out what it was. . .

Just a thought. . .
 

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Discussion Starter · #4 ·
I narrowed it down between the ecu and the fuse box.....thanks for the tip Im going to check for burnt or melted wires.

the car turns on sometimes,but dies out once is warmed and I give it throttle...it just keeps blowin the EFI fuse.
 

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HMOOB VWJ NYOB MINNESOTA
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I narrowed it down between the ecu and the fuse box.....thanks for the tip Im going to check for burnt or melted wires.

the car turns on sometimes,but dies out once is warmed and I give it throttle...it just keeps blowin the EFI fuse.

1. Check your fuel system wiring especially fuel pump.
2. Check 02 sensor wires
3. check injector wiring ( resister )
 

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Discussion Starter · #6 ·
I disconnected all injector plugs and resistor box.....fuse still pops when I turn the key


the only thing I can narrow it down to is the ecu because when i disconnect it and turn the key to acc the fuse does not pop.Now here is the thing the ecu is sharing 12v power with the safc,boost controller,and boost gauge....I disconnect the afr gauge,so thats ruled out.

I checked the o2 wires and 2 were slightly melted....I went ahead clean them up and rewrapped them.Replaced the fuse and turned the key and the fuse pops again.
 

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Discussion Starter · #7 ·
Ok looks like is coming from the harness.....I disconnected the ecu,all injectors,resistor box,fuel pump....replaced the fuse,turned the key...fuse pops again.

The only thing I can think of is the wiring to the safc...im going to have to go through it to see if i can fine a bad wire.
 

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Discussion Starter · #8 ·
Problem solved.....found a wire in the injector harness that was open and making contact with the intake mani causing the EFI fuse to pop.

Car runs like a champ now.....appreciate the help guys
 

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greasemonkey
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check the 5v+ line for the tps, o2 sensor, maf, etc... if any are low, then that line is shorted to ground somewhere and will blow the fuse. i had an issue once where the o2 sensor wires somehow touched my dp and melted and popped the efi fuse.
 

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I had a similar problem that left me stranded several times. Anytime I put load on the car it would blow EFI-1. After many experts, it was determined to be the MAF which was shorting out.

Good Luck
 

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For some reason I keep blowing the efi 30amp fuse.....the car is a 98 sc300,soarer 1jz/r154 swap,single turbo, 550 mk4 injectors with a resistor from a Acura TL installed a few months ago and never had any isues.The other day I was cruising at 40mph and the car shut off,no sound from the fuel pump.I fine the efi fuse blown,I go ahead and replace the 30amp fuse,it blows again as soon as I turn the key to ACC. I have tried different steps to pin point the problem...but no luck -I disconnected the resistor to check if it is causing the issue,fuse pops again as soon as I turn the keep. -Disconnected all injector plugs,it pops agin once the key turn -Disconnected the ecu....fuse pops again If anyone can help me out please give me some info as to what maybe causing this random problem
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