My fuel injector fuse in the haltech fuse block blew out. I was driving down the highway Sunday. I slowed down, exited the highway and began driving on a regular street. I pressed the gas pedal and the car wouldn't accelerate. I replaced the fuse and drove to work today (Tuesday). Got there with no problems, but the same thing happened on the way home from work. Driving slow in the rain, just made it to the top of a hill and was on a level road with the throttle pressed slightly and all of a sudden the car died. I autocross the car and so it sees harder driving conditions then these, yet i've never had a problem until Sunday and tonight. I've had this setup for over a year. Its a S4 NA with 460cc primaries and 720cc secondaries. I inspected the wire harness and didn't see and chaffing or exposed wires, but I will look again tomorrow just to make sure. Besides a wire short to ground, what else would cause this? Faulty injector(s)? Over heating injector(s)? The engine doesn't overheat. I'll provide any info I can to aid someone in helping me fix this.

 

Update: I reinspected the wire harness and I found that a grey w/red strip wire was loose from the rest of the harness and it was hanging down touching exhaust manifold. The shielding was melted and the wire was exposed. According to the haltech manual, all the grey/red 18ga wires are 13.8V inj wires. I'm assuming that this is the source of the problem since I was unable to find any other defects. If anyone has anything else they think I should check, feel free to post it here and I will check it out asap.

 

90% of blown fuses are a result of a grounding problem... Looks like you found yours!!!!

 

That is correct.
If you ever tore apart the Haltech harness, you'll find that all the wires bunch into a single lead somewhere in the middle.

All +12VDC switched are basically on the same circuit.


-Ted