Stock fuel pump is NOT doing good. Fuel pressure is dropping to ~10psi under WOT operation or whenever pulsewidths get fast enough like entering PE mode.
So it's now confirmed...I NEED a new fuel pump. Forget about trying to pump 330hp out of the stock one unless you've got huge 90# injectors and only have to run with ~10psi, else go with Walbro.

 

How are you gonna do it? Cuttin' a hole or dropping that tank?

 

Depends on where I get help. If at home I'll cut the hole, if at school I'll drop the tank. The trouble is that I NEED to do this in one day because I work every other day at least.

 

Jon, I was able to put my Walbro pump in the correct way in about 4hrs by myself. So you are a lot younger than I am so you should be able to do it in 4-6hrs easily. I shouldn't say easily. Its a PITA. Just make sure and cut the exhaust where its easy to patch or I believe some have done it by just disconnecting everything up to that cat and let it lie on the ground. I replaced my exhaust at the same time so it didn't matter to me. But you should go ahead and change it while its still pumping or if you have my luck it will quit while the tank is full of gas.

 

I didnt have to cut my exhaust when I did it. I just took the tires off and it moved out of the way just far enough. You definetly should be able to do it in one day even by yourself. It isnt that bad. Hardest part is breaking bolts loose.

With my current exhaust setup it will be easier because i wont have to worry about dropping the exhaust

 

man..i am just WAITING for my fuel pump to crap the bed. i have my 80 pound injectors at about 18 psi at WOT and the fuel pump is still running strong, but i have a feeling that i am on borrowed time.

keep us updated on what you end up doing. i think it will be in my best interests to get a new pump over the winter.

-brian

 

my car is screwin up now, i think its the fuel pump.. It'll start, the fuel pump primes, then the car dies. Every time! It did it once before, and the day i was gonna go and buy a new pump it started working. Luckily, it was full on gas that time... this time i have about half a tank.. still not good but better. Is there an easy way to get to the wires to check voltage before i drop the tank buy a new pump and take **** apart? If so what wires and how do i get to them?

Thnx

 

I like the pump i got, vortec truck pump
42 gph at 36 psi.. you can get it at the parts store
fits and looks exactly like stock

 

Interesting, I read that you did that in another post. How much did it cost you? I've already got a 255lp walbro I'm getting for $70 brand new. I can't pass up the deal unless the truck pump was cheaper. Even then I think I want to go with the walbro just incase N2o or cam/engine work this summer.
Let's say the vortec motor flowed 50gph at 20psi, that's the same as the 190lph walbro (slightly less) but still it's enough for 400+hp.

 

Does the Walbro 255 require any modification to fit, or does it go right on?

 

Like a glove! It's a standard intake pump, just reuse the hanger and the kit comes with the standard GM hardware and pickupscreen.

 

Ah, this is good news. I want to change mine over xmas break when I swap rear ends. 120k on the stocker, heh runnin on borrowed time I reckon.

Maybe if a bunch of us are getting them we can setup a group purchase? I can talk to my friend who owns a shop and see what she can do for a price if you guys want.

 

If the vortec fuel pump is a good install you could save BIG bucks getting a used one from a 96-98 truck with the 5.7 vortec. Actually any of those pumps should work (they're GM universal)...the hangers are really the unique parts, not the pump itself.
If you don't mind trying a used pump (I know I don't) then go to www.car-parts.com and do a search for fuel pumps, 1996, any 5.7L truck. If you scroll through the pages you'll see some listed for only $20. Even if you got 3 of em you'd sure to have at least 2 good for 250k+ miles if not more. I would have done this earlier if I had known, instead I already told the guy I would buy it from him so it's pretty much a done deal.
Even with a group buy you won't be able to beat this guys prices on the walbro pumps.
http://www.autoperformanceengineerin.../fuelpump.html

 

jon, where are you going to get yours? i think it will be a worthwhile investement for me to get one too.

either that, or MAYBE the truck one.

-brian

 

Somebody would have to be nuts to go through all that work to change pumps and put a used one in. I guess if your flat broke and have a lot of time on your hands but I have put that pump in and I hope this Walbro pump lasts the life of the car because I don't want to do it again. I rank it right there with putting the headers on a thirdgen. Not as many busted knuckles though. I have right at 20k miles on my Walbro now and no problems.

 

Just out of curiosity, are you sure the pump is bad? I had the exact same trouble with mine, and all it turned out to be was a dirty fuel filter. Car was fine except under WOT. That pump now has 220,000+ on it and still ticking....

just a thought before you tear into that tank. I was ready to do the same...

 

Jon, awesome heads up on that site.

I wanna leave open the possibility to go to a high hp 8 injector setup in the future so I wouldnt mind having the high pressure pump, pn FPG003, but would this be too much for the tbi fpr? I know people have posted the standard 255, pn FPG002, works fine, but I dont think I've read about the higher pressure one.

 

For $20 and knowing that the pump works even after being "used" is good enough for me to grab a couple. The only issue is like you said, time. I've heard a few stories about the walbro pumps going bad and in just about EVER case of ANY fuel pump going bad it was either the driver running on a 1/8 tank all the time or bad wiring and not getting enough volts. It's rare that a fuel pump just quits when you think of it's simplicity in parts. Either they work or they don't. Same goes for electronic parts (ESC modules, ecms, etc). They never go bad unless you do some stupid stuff.
As far as getting my pump, it's from a local guy back home.
The 255lph pump just means more fuel will flow through the system and so the return line will get a LOT of fuel back at idle. If there is a problem with fuel pressure creaping up at idle I'm sure it can be fixed with some new fuel line and a 3 port external pressure regulator. Hopefully that doesn't happen and I doubt it will but worst case...
Brian, have you actually put your fuel pressure guage on the hood so you can see what it's doing with high engine load on the highway? I spent about $7 in parts from Lowe's to relocate the fuel pressure guage to the hood. If you're interested in doing it you need to buy/get 2 hose clamps, fuel line (they have that too), the 1/8" male fitting to 1/4" female adaptor, a 1/8" female to 1/4" female adaptor, and 2 1/4" barb fittings for the fuel line. Once you do that, just t it right into the stock location fitting with some teflon table and you're good. Maybe some duct table to hold in on the windshield yes that's how I did it.
When you prime the pump you'll see the pressure go up and when you start the pressure should go down quick and back up, especially if your vacuum AFPR is working properly.
As for the fuel filter...I replaced it less than a year ago and have driven only 10k miles on it so I doubt that's the problem. I'll change it again since it's only $3. If that's the problem then I'm still getting the walbro. I can't pass up the $70 deal and I do want to do some N2o this summer. A 100hp shot hehehe.

 

I took my tank out and came to find out the wiring was damaged on the pump on my TA, so I repaired the wiring and threw everything back in the car. It lasted another couple years before it completely kicked the bucket. Throwing in a used pump if you are really tight for cash... I could see someone doing that.

Jon, as for your car... if you cut a hole in it to replace the pump, I am going to come to your house and personally smack you upside the head. It is not that hard to drop the tank and do it the right way. I did it in my driveway, by myself, with 2 jackstands and one jack. I didnt cut the i-pipe, I just moved it around a bit and yanked it out from under the car. Just be careful with the brake line from the body to the diff. I think I spent around 6 hours the first time, and I was taking my time. You shouldnt have any problem doing it in a day unless your car is a rustbucket and doesnt want to give up any of the track bar and tank strap bolts.

 

I'll drop the tank, .
Max, it's usually me telling people that I'm going to reach through the monitor and smack them. You took it to the next step by doing it in person....ouch.
I've got friends that have lifts etc. that I can use for free and get free working hands so it should be pretty easy.

 

The worst I've heard about is rusted bolts. You might run into that on your car, given where you live. Might want to spray them now with something to break down the rust, and just spray it every few days for a week or so, it'll make it easier if there is a problem with them.

 

im pretty sure the fuel pump isnt doin its job right now in my car, it starts then dies real quick, can hear the pump priming, but no gas to the engine.. you guys think i should drop the tank and check wiring before i go to replace it?

 

The mallory 3 port fuel pressure reg is nice. Im running it on my car. I have a new stock replacement pump and Im regulating that down to 5psi. With the mallory the pressure stays at 5psi and never moves. It works nicely.

 

you're running 5psi??!?!?!?! with TBI??!@?@@!!!

 

Easy there Corky, he has a carb.

 

"holley 670cfm street avenger"
lol, I read only the one line....avenger was on the other line

 

its ok jon, i did the same thing.

-brian

 

So I walk out to my not working car last night, me and my friends were heading to a movie. I decided to try to start the car another time, just to see if by some weird fluke it works. Well before when i started it, it would start as normal then the rev's wouldnt stay up, they would drop (faster if i touched the gas too). Well this time i go to start it, and its having trouble turning over... then i try again and after a few attempts i manage to get it to turn over, then it runs fine... so my cars working, but i didnt do anything.. what do u guys think i should get checked? fuel pump and wires is what i was thinking, but its weird that it fixed itself.