Jon82387

Hey guys just recently got my mustang back together after installing a TKO 600 and finally getting the transmission crossmember welded. Well i went out for a cruise today to test things out a bit and im having a problem when i go from 1st to 2nd gear and hit about 3500RPM. The car will just shut down and im almost 100% positive its the fuel pump shutting off for some reason, ill get to like 3500RPM in 2nd gear and the car will die so i checked the inertia switch in the back it seemed to be fine, unplugged my relay under the seat and wiggled/checked connections at the fuse box and nothing really fixed it (all while on the side of the road) then after about 10-15 minutes i can turn it over and it will finally start.

When the car dies and i try starting it it will just crank and not start, also i turn the key off and on and i really cant hear the pump like normal but when it eventually does start i really cant hear the pump then either.

The pump is about 2 years old its a BBK 190LPH pump. Im going to try changing the relay 2marrow and see what happens anyone else have any ideas??? I searched the forum and couldnt come up with much.

Thanks Jon

mjr46

you need to hook a fuel pressure gauge up to it if you suspect that and tape it to windshield and watch what pressure does under hard accel, if it is the prob, it'll drop of and you'll have your verification.

Jon82387

the fuel pressure thing just seems odd b/c its acting like the whole pump is just dying off at once no gradual cut off, i do have a f/p gauge underhood but i guess that doesnt help much under accel. The car runs fine as long as im not shifting it really hard ><

Also i didnt think of this b4 but since i do have a gauge underhood if this happens again and i actually check the gauge(didnt even think to do that) what readings should i be getting??? say the fuel pump is totally cut off for some reason would i have 0 FP after this happens?

mjr46

when you go to WOT pressure will be bumped up to around 38-40 and stay there while under hard accel, however, if it drastically drops under hard accel, you have a supply/volume issue

Jon82387

Well i found the problem today, i changed the relay just for the heck of it then i started it and was about to pull out of the garage and i bumped some of the wiring harnesses on the driver side kick panel and it started to cut off and die. So i get my chilton's manual to check out the wiring diagrams to see if i can pinpoint which harness goes to the fuel pump and found one of the harnesses and pulled a wire out of it that was corroded and had broke off of the pin. Wire had a hell of a hiding spot i'll say that much.

Spliced it back together all good now =D