Fuel pressure zero after oops

nwb300

Member
I needed some time to cool off after this stupid mistake. I was installing an after market fuel gauge and had had the battery disconnected like i'm supposed too. Released the pressure from the fuel line and then removed the schrader valve and installed the gauge. After I hooked up the battery I pressured up the fuel line and I didn't like the angle the gauge was so I got my trusty wrench out and when I went to turn down the gauge I bumped the wrench handle on the back of the alternator and it sparked :eek: I know I know.....I should of unhooked the battery but I didn't. I had pressure but after this I tried starting the car and it wants to turn over but wont start and my fuel pressure reads 0. The only things I have checked so far is the inline fuse and that seemed ok. I looked at the relay under the back bumper and it looks ok. Haven't looked under the dash to see if any fuses are blown. Any suggestions on what else to check?
 

whitehot1

Well-Known Member
I needed some time to cool off after this stupid mistake. I was installing an after market fuel gauge and had had the battery disconnected like i'm supposed too. Released the pressure from the fuel line and then removed the schrader valve and installed the gauge. After I hooked up the battery I pressured up the fuel line and I didn't like the angle the gauge was so I got my trusty wrench out and when I went to turn down the gauge I bumped the wrench handle on the back of the alternator and it sparked :eek: I know I know.....I should of unhooked the battery but I didn't. I had pressure but after this I tried starting the car and it wants to turn over but wont start and my fuel pressure reads 0. The only things I have checked so far is the inline fuse and that seemed ok. I looked at the relay under the back bumper and it looks ok. Haven't looked under the dash to see if any fuses are blown. Any suggestions on what else to check?

You really should have looked under the dash for the blown fuse.;)

Most likely that is what happened when you hit the battery terminal lug on the back of the alternator.

I've done that a couple of times in my life too, so don't feel like your're the only one to ever do this. It happens!! :smile:
 

novaderrik

Well-Known Member
look at the fuses under the dash- i think the one you want is labeled "F/P"..
you say you have a relay under the rear bumper- that means a hotiwre kit.. if it's an aftermarket kit, then you've got an inline fues somewhere in the vicinity of the alternator. my kit has the fuse screwed right to the back of the alternator. check that.
 

nwb300

Member
I checked the fuse under the dash labeled "f/p inj" and it was a 15amp fuse and it was good. I do have a hotwire kit and that was the first thing I check was the 30amp fuse mounted to the firewall and it was good. The car was running after I put the gauge on I just wanted to adjust it. How can I tell if the 30amp relay under the bumper is bad? Or do I just have to replace it to find out?
 

whitehot1

Well-Known Member
I checked the fuse under the dash labeled "f/p inj" and it was a 15amp fuse and it was good. I do have a hotwire kit and that was the first thing I check was the 30amp fuse mounted to the firewall and it was good. The car was running after I put the gauge on I just wanted to adjust it. How can I tell if the 30amp relay under the bumper is bad? Or do I just have to replace it to find out?

Do you have a test light? I believe there are other fuses that could have blown that could be the problem, check / test them all.

I've seen fuses that looked good but tested bad.

If you don't have a tester use a new fuse to test with.
 

nwb300

Member
I'll give that a try. I can't find my box of fuses so i'm going to run to the store and buy that fuse kit that comes with a tester.
 

TR Custom Parts

Mark Hueffman - Owner
That's exactly why we warn to disconnect the battery when installing our kit. Just too easy to do what you did, especially if the cover is missing on the back of the alternator. Have a friend who made this mistake while wearing a metal wristband watch. Only problem is the watch became welded to the alternator stud and burned the crap out of his wrist. Got to be careful!
 

TurboBuRick

Moderator
Staff member
Lucky no fuel was on the intake.:eek:

The fuel pump hot wire comes off the alternator and usually has a in line fuse a few inches down the way.
 

GNVenom

Well-Known Member
Check your battery positive cable. That stud wiring goes directly to the battery, no where else.

A dead short could possibly destroy the cable feed. It can't blow a fuse.
 

Phoneguy

Cometic HG stress tester
Lucky no fuel was on the intake.:eek:

Last year at Richard Clarks, as my car was being put on the dyno the guy operating the dyno moved my fuel gauge ( with a 2' braided steel line ) to the windshield of my car and arced the fuel line to the alternator causing a LARGE fireball under my hood while my son was under the hood!!! Fuel and sparks dont play well in un confined spaces.


Bryan
 

jjkv

Member
I needed some time to cool off after this stupid mistake. I was installing an after market fuel gauge and had had the battery disconnected like i'm supposed too. Released the pressure from the fuel line and then removed the schrader valve and installed the gauge. After I hooked up the battery I pressured up the fuel line and I didn't like the angle the gauge was so I got my trusty wrench out and when I went to turn down the gauge I bumped the wrench handle on the back of the alternator and it sparked :eek: I know I know.....I should of unhooked the battery but I didn't. I had pressure but after this I tried starting the car and it wants to turn over but wont start and my fuel pressure reads 0. The only things I have checked so far is the inline fuse and that seemed ok. I looked at the relay under the back bumper and it looks ok. Haven't looked under the dash to see if any fuses are blown. Any suggestions on what else to check?

if you have checked all the fuses in the fuse box....One last place to check is the Fusable Links located under the car and attached to the starter....John
 

nwb300

Member
I won't get a chance to look at it today. I can't even explain the weather going on outside right now. LOL I'll look at it tomorrow and list everything I check so we can narrow down what it could be. Going to buy more fuses tonight and go from there. Thanks for all the input so far!!!!!!
 

nwb300

Member
Well, I finally got around to checking it out. Comes to find out there was a inline fuse on the cable that goes from the alternator to the battery (previous owner must have put it on). Went to advanced auto and got a new cable and bam its running again. Now I just need to dial in the fuel pressure. Its at 35 with the vacuum on. Thanks again everybody for you input!!!!!!!!!!!!!
 

whitehot1

Well-Known Member
Well, I finally got around to checking it out. Comes to find out there was a inline fuse on the cable that goes from the alternator to the battery (previous owner must have put it on). Went to advanced auto and got a new cable and bam its running again. Now I just need to dial in the fuel pressure. Its at 35 with the vacuum on. Thanks again everybody for you input!!!!!!!!!!!!!

Glad you got it fixed.

I've never heard of anyone putting an inline fuse on the alt to battery charge wire before, it doesn't sound like a good idea though.

My fuel pressure is at 35 psi also with the vacuum line on and 45 psi with it off, thats what the recommended setting is with my extender pro chip with 60lb injectors.
 
Top