FP issues.........HELP.

[sharkbait]

PLEASE help me or someone send me a box of tissues so I can cry in the corner of my garage!

here's the back round story.

trucks been on E85 for some time. Braided line/AN fitting A1000,code59, blah blah blah changed to the braided Teflon line/AN fitting for the E85. truck was running and driving perfect.

truck was running great....until
the truck would run for 2 or 3 mins and then FP would drop drop drop and wouldn't run.

I would let it sit for 30/45 mins and it would start fine, 60psi....drop drop drop fp and die.....one of my cheaper thougths was the A1000 regulator. the diapram looked kinda crappy. so I replaced it. junk. same thing.

I figured it was the pump. had my A1000 rebuilt to like new specs. the e85 killed it they said. I was told by Aeromotive that it was an old model pump and the e85 was too much for it.

the truck was running but needed fuel on the fuel tables (code59) so I put it in the garage for the week (a month ago)

went into the garage to start the truck to log so I can add some fuel.........NO FP. it wouldn't go on. no prime no nothing......

so I checked all the fuses in the dash. 95 s10 location. good

checked the alternator fuse. good.

I have a fuel pump relay (racetronix) under by the roll pan. had a new one in the garage. changed it. no good.

I have two relays on the firewall on the pass side where the ignition coil/map sensor is. replaced them. nothing

I have two relays on the driver side firewall, replaced them. nothing.


so when I turn the key to the on position I can hear the racetronix relay click on, then off. if I crank the motor for a second no FP.



SO SOMEONE GIVE ME A SUGGESTION PLEASE. Im thinking its something silly that im missing. I was never an electronics guy, but ive tried all that I can think of.

 

[sharkbait]

Re: FP issues.........HELP.

over the two months I hope I put everything in proper order.

 

[Sy#1991]

Re: FP issues.........HELP.

Have you checked for a good 12 volt and ground at the fuel pump? If you have that at the pump it should come on, if not than the pump maybe bad.

 

[mattw]

Re: FP issues.........HELP.

so when I turn the key to the on position I can hear the racetronix relay click on, then off. if I crank the motor for a second no FP.



SO SOMEONE GIVE ME A SUGGESTION PLEASE. Im thinking its something silly that im missing. I was never an electronics guy, but ive tried all that I can think of.

Does the pump come on and does it build fuel pressure when you hear the relay click?

 

[sharkbait]

Re: FP issues.........HELP.

Does the pump come on and does it build fuel pressure when you hear the relay click?

no. just the relay clicks. then clicks 3 seconds. clicks and that's it. Im alone so I probably should test juice at the pump when the key goes to position ? see it its a pump problem? it IS new now and was working.

 

[sharkbait]

Re: FP issues.........HELP.

If this is the "standard" SyTy racetronics set-up, putting +12V on the test terminal will trigger the racetrronics relay at the fuel pmp, and make the pump run.

Jump the test terminal.
Check for 12 V at the big red wire at the racetronics relay. If = No, check the fuse at alternator again.
Un-plug the racetronics relay by the pump. It should click, unclick, when you plug it in or remove it. If = No, check for +12V on the grey SyTy wire, through the connector, to the relay pin. If grey wire OK, check that the relay is grounded.
And finally check that the output to the pump has +12V. If it does, the pump died again.

alternator fuse (right behind alt) is good. it did have juice on the thick red power wire on the racetronics relay.

I will put some power to the pump and see when the key goes to on posision it gets juice to prime. if that is the case, yes, it is the pump being toast.

 

[sharkbait]

Re: FP issues.........HELP.

If this is the "standard" SyTy racetronics set-up, putting +12V on the test terminal will trigger the racetrronics relay at the fuel pmp, and make the pump run.

Jump the test terminal.
Check for 12 V at the big red wire at the racetronics relay. If = No, check the fuse at alternator again.
Un-plug the racetronics relay by the pump. It should click, unclick, when you plug it in or remove it. If = No, check for +12V on the grey SyTy wire, through the connector, to the relay pin. If grey wire OK, check that the relay is grounded.
And finally check that the output to the pump has +12V. If it does, the pump died again.

what is "jump the test terminal"?

 

[sharkbait]

Re: FP issues.........HELP.

ok. no juice at the pump under any trickery. lol.

the big red wire to the racetronics relay does have juice when I have the key in the on position.

 

[mattw]

Re: FP issues.........HELP.

So it sounds like:

- You have confirmed you have power going to the relay.
- You have verified that the relay is energizing as you can hear it clicking
- You have no power at the pump even when the relay is active..

If all of the above is true you either have a bad relay or there is an issue with the wiring between the relay and the pump..

 

[gringo76]

Re: FP issues.........HELP.

ya if power is going into relay check power coming out of relay when it click. if there is power going out, you got a wiring problem to pump or ground problem. just run a hot wire from batt straight to positive side of pump just to see if it spins to eliminate that.

 

[sharkbait]

Re: FP issues.........HELP.

ok, im going to bed. 1030pm. im tired. lol.

these are my findings......

I ran a jumper cable from the battery and jumped the test plug coming outta the loom on the pass side. nothing.

I have juice into the racetronics relay.....tried to jump the opposite purple wire that powers the pump. I got a spark. let go very quick. lol. no pump turning on.

put a light tester to the positive of the FP, had my son put the ignition key in the prime position.....JUICE. but I didn't turn on. the tinny wire I was using with the little momentary switch got super hot real quick.

I jumped the positive right to the positive of the FP from the battery. NOTHING. its starting to sound like the pump is frozen? like the last time it ran, and then sat, it froze? weird. heated garage. and the past month has been nice and warm............im going to sleep.

keep your thoughts coming syty.net.

and thanks!!!!!!!!!!!!

 

[BstedElky]

Re: FP issues.........HELP.

Sounds like a fried fuel pump. Next step, drop the tank and pull the pump. Make sure you disconn. the battery so you don't have a fireball.

 

[gringo76]

Re: FP issues.........HELP.

that would be my guess, bad pump if you got power to it. only other poss thing would be bad ground. you can just hook a test light to positive side of batt and probe the ground post of pump, if it lights up you got good ground but sounds like you got a frozen pump.

 

[IGottaSy]

Re: FP issues.........HELP.

Can u use a fuel pump from a newer vehicle in these tanks? Some of the big cube ls engine are running on e85 and making good power in stock form

 

[sharkbait]

Re: FP issues.........HELP.

that would be my guess, bad pump if you got power to it. only other poss thing would be bad ground. you can just hook a test light to positive side of batt and probe the ground post of pump, if it lights up you got good ground but sounds like you got a frozen pump.

yeah. im thinking im going to do that. I was using the ground the racetronics was grounded to and the 12volt light was going on when I was testing the racetronics relay and the fuel pump.

now that I think about it it kinda makes sense that the pump was acting up. the AFRs were way off. which made me think something was off with the fuel line, ie clogged filter/etc.

so today I will drain the tank. and pull the pump. its external. so no biggie but I have 10gallons of E85 in the cell. so I will drain it and put it in my two gas cans. save it for the spring.


on the E85 topic I have read that guys will put just a little regular gas in and run the car for a minute or two. just to keep the alcohol from sitting in the lines/injectors etc. it will run pig rich unless I swap the tune to the gas tune. but that pumps gotta go back. AGAIN.

 

[sharkbait]

Re: FP issues.........HELP.

thanks for talking me through guys.

 

[BstedElky]

Re: FP issues.........HELP.

Glad you figured it out. Good luck when you get to replacing it.

 

[sharkbait]

Re: FP issues.........HELP.

last three years has made me "glass is half full" kinda guy..........it could have lost FP under boost.........KABOOOOOOMMMMMMM.

 

[BstedElky]

Re: FP issues.........HELP.

I thought I had a bad fuel pump on the Elky (pre-typhoon) turned out it was the tank I have (spectre after market doesn't have baffles), so when it gets low, the pickup goes dry...

 

[sharkbait]

Re: FP issues.........HELP.

Can u use a fuel pump from a newer vehicle in these tanks? Some of the big cube ls engine are running on e85 and making good power in stock form

its a external in-line pump. I have fuel cell between the chassis in the spot of the spare tire.

(if you check my build thread youll see it)