Fueling & Injection - fuel pump not priming ?

when i turn the key my fuel pump is not priming
need my car running asap so if any 1 can help me out with this would be greatly appreciated

back ground info, car has been sitting for 3-4 years with 1/4 tank of gas in it

just replaced:new gaskets on the intake, starter, battery, egr & air delete, replaced torque converter, and u-joint. prob none of this is related to the cause but just encase i figured why not post it


in worse case pump is bad also what pump would you recommend
im thinking bout the f99 from racetronix but i seem to not be able to find any good reviews bout it ?


***UPDATE: ***
alright found bad fuse idk if it popped during jumping wires, or if it was over looked when my friend said he checked it but now im getting power to the pump, but the pump is not kicking on

and the sending unit is only getting bout 8 volts idk if this is normal ?

no 1 knows what could cause this ?

Have you checked the fuse?

I checked the fuses inside

I checked the fuses inside

Check the one under the hood. That is where the fuse for the pump is.

Its still good

Well unless you have a test light or a multimeter there isn't too much more you can check. You said it was sitting for 3 years. Maybe a mouse climbed up on your tank and ate through some wires. That did happen to me but only ate through the fuel level wire. You could check the connection coming out of your car above the axle and going to the tank. However it's probably just a bad pump.

I put in the Walbro 255 with a racetronix hot wire kit a few years ago and it's been good so far. Hope this helps

my car did sit kinda in the woods for a bout a year on my friends property
and i have access to a volt meter what and where do i need to test

i was thinking bout the ractronix f99 and the Casper hot wire kit

where to i need to hook up the volt meter to test my relay and harness ? to make sure im getting power to the pump ?

my car did sit kinda in the woods for a bout a year on my friends property
and i have access to a volt meter what and where do i need to test

i was thinking bout the ractronix f99 and the Casper hot wire kit

There are a few places you need to check. I like to go straight to the pump and check for power there first. It isnt something you can do unless the tank is dropped or you have an access hole cut into the top. You could check for power at the fuse and then make sure the fuel pump relay is engaging. The relay is also located in the engine compartment. Then you can check the connector located above the axle. They are easy to spot and are on the drivers side of the car. I am pretty sure it's a gray wire that powers the pump.

I am not an expert in fuel pumps, but I am sure a lot of people on this forum use recetronix. I have never heard of the Casper hot wire kit. I use the racetronix one myself. It was extremely simple to install as long as you have access to the pump and the vehicle is off the ground. I'm sure the Casper one is just as easy.

thank you good sir, this is the kinda info i have been looking for, ok so if im not getting power at the grey wire and the fuse is good, does this mean the relay is bad ?

It's no problem at all. It's very possible the relay is bad. I am not looking at it now but I think the AC compressure relay is the same as the fuel pump. If so, trying switching them out to see if the pump comes on.

AC compressor.... got ahead of myself on that one. When you are doing this are you turning the ignition on while monitoring the mulitimeter? The car only primes the fuel pump for a few seconds when you do this. So just to make sure, you need to be watching when you just turn the key. You should definitely have power going to and from the fuse. From there it goes to the relay. The relay then gets power from the PCM once the key is turned on. This power activates a coil inside the relay allowing the power that was coming from the fuse to pass through the relay. It leaves the realy through the gray wire that goes to the pump. Trying to give you a better understanding so you can troubleshoot this a little easier. Hope this isnt too confusing and also helps.

it got to dark to check, im going to have to check this out tomorrow after work, this definitely helps me out a lot, and jus wondering since the fuel pump only primes for a few seconds i wouldn't be able to drain the tank this way would i ?

That might be a pain to do it that way. When I drained my tank I took the supply line off of the fuel filter and the ran a jumper wire on the fuel pump relay. This kept the pump running as long as I wanted it to. I also had a friend watch the fuel level in the bucket so I didnt have any spill out. You could also siphon it out of the tank through the filler tube.

o good idea, i asked my friend if i could siphon it out but he said it would not siphon threw the pump or something, but which pins do i need to jump to do this ?

ok so i just took a wire and connected it to terminal 85 on the relay and jumped it to the 12volt aux jump point near the fuse box, when i turn the ignition and lesson under my car where i have the fuel line disconnected from the filter i can hear it bubbling but not gas is coming out of the line

I had an issue like this once where my car just stop running. Turns out it was one of my grounds.

nvm on that last post now its not making any sound when i do it

really cause last time i drove my car it just kinda powered down, is there a way to find out if i have a bad ground ? but 1 of the starter mounts had broken off some how lol, so i figured that was the cause of the car stopping

I just put a jumper wire on 87 and 30. As long as power is going through the fuse and to the relay then you should be getting power across the jumper and to the pump. Just check either 87 or 30 for power. I can't remember which one should have it. After you put on the jumper you should hear your pump running. If it doesn't then either your pump is bad or power isn't making it to it. If the pump does run then you need to troubleshoot your relay. If the relay is good then I would assume it has something to do with your PCM. Not too sure though.

It's a good thing My6SpeedZ stepped in because I didn't even think about the grounds. Can your multimeter do continuity check? That would be an easy way to check your grounds.

would i do that test at the back of the car see how strong the signal is ?

You might as well check your power first. When checking your ground you will check the resistance of the wire or check continuity. Did the pump come on when you used the jumper? If not check for power at the jumper then the gray wire closest to the pump. We need to be sure power is getting to the pump before we check anything else.
Check power on both sides of the fuse. Remove the relay and install jumper at 87 to 30. Check for power at both. If you still have power check power at the connector above the axle. Let us know what you have from there.

kk i just got off work a bit ago so im going to check all this in the AM,

i think im going to go ahead and order that pump and wire kick cause if my wiring bad, im going to need it any way, an ill be right there at the pump so i might as well get it too while im at it what you think ?

I will probably end up being a bad pump. But those wire kits still need the existing wiring harness to work.

jumped 30 - 85 with and without relay pump still not on just gotta get under the car and test the volts back there now

o yeah was thinking it didnt matter but i forgot that they clip in all the way back at the pump

so i guess im bout to order this pump i just ordered the wiring figured i probably needed it any way, u think i should go with the stock replacement or the upgrade 122 vs 160, but i probably wont hit 600 hp any time in the near future

dude on here says he got the upgraded 1 for 125 shipped think i should go with that ? idk tho low number of post so kinda weary

Jumping those with the relay out won't help you at all. If you are going to jump anything with it out it needs to be 30 and 87. Did you check for power at the connector in the back when you jumped it with the relay in?

Do you have someone that can turn the key on while you check for power at the connector in the back? If so then put the relay back in (make sure it's in right) and one person turn on the key while the other checks for power.

The wire kits for the fuel pump allows less of a voltage drop to the fuel pump allowing for more flow and pressure for upgraded pumps. I think the stock wiring is ok with a stock pump. But if you do decide to upgrade your pump then you should get the wiring harness as well. Just my opinion.

i didnt have any 1 to help me test the voltage today so i was unable to do that, hopefully my brother will be here tomorrow and be able to help me out with it

Ok. You can always take the relay out and put the jumper wire on 30 and 87 and see if the pump comes on. If not check power at the connector.

ok bout to cut out the trap door, and test all the wires, wish me luck lol

trap door is cut, came out better then i expected bout to test the wires see if its getting steady voltage

ok so grey wire at pump is only getting power when 30 is jumped to 85 on the relay, this is the connector the directly plugs into the pump on top the gas tank

and the sending unit is only getting bout 8 volts

also tried swapping all 3 relays still no power back to the pump unless i jump 30 - 85

well turns out the fuel pump was bad i finaly checked it myself instead of just taking my friend word that is was good when he checked it, well it was bad, so now there power to the grey wire at the pump but it is still not kicking on

well turns out the fuel pump was bad i finaly checked it myself instead of just taking my friend word that is was good when he checked it, well it was bad, so now there power to the grey wire at the pump but it is still not kicking on

Awesome. So a new pump will do the trick. How did the hole come out? Mine was a disaster when I did it.

Sorry I didn't see that you had commented on it.

its all good man, the hole came out really well, went to my friends shop and cut a piece out bout half inch bigger on each side to cover the whole with, ill post a pic lil later when i get home. i ordered the pump and wiring kit already in anticipation of the pump being bad, so should be here in the next few days, cant wait for it to get here paid 30 bucks for 3 day shipping from racetronix pretty ridiculous if u ask me but its what ever lol.

i was thinking while im here i might make a whole actual trap door kit out of diamond plate with a twist turn lock and a hinge or something what u think ?

so seeing how im now getting power back there, it is for sure the pump right. just making sure ?

oops just noticed i worded that wrong in that post u quoted, but the same result im sure. i meant to say the fuse was bad after finally checking it myself instead of taking my friends word for it when he checked it, so now im getting power to the pump but it is not kicking on regardless so im pretty sure its bad

my trap door mod =] . first time using a cut off wheel as well
http://i1245.photobucket.com/albums/gg584/devic45/2012-07-11_184339.jpg

If you're getting power to the pump then the pump is bad or you have a bad ground. I'm sure it's just a bad pump.

You need to make sure you post some pics of that hinged door when you get it done.

ok well i got the new racetronix pump in, new fuel filter, but im only getting 40 psi at the rail.

and the car will not bust over im only getting spark to certain plugs ?
when i first turn the key it trys to start then stops, i tried switching the coil packs but nothing

and i differently will but im prob not going to work on that till after i get everything working right

Around 40psi is what you should be getting until the car is running.

What do you mean by it tries to start then stops? Does the engine stop turning over? Has that battery been sitting for 3 years too?

You check spark at every plug while turning it over?

i gets spark and gas for a moment, then it jus turns over

i started a more generalized threads to try and find the problem if its not dealing with fuel perhaps now, if you continue with ur greatly appreciated help on this page i would be great full good sir

full details on my car in this link
http://ls1tech.com/forums/generation-iii-external-engine/1564986-car-wont-crank-need-help-asap-plz-need-car-moved-asap.html