any advice on a fuel pump replacement?

[94LT1Z28]

For roughly 2 weeks I have been working on my car and I have finally found the problem. It turned out to be intermitent, but it is the fuel pump. I left a fuel pressure guage on it. When the car started running like crap it was getting about 5-8 psi with key on. With the car running it would jump to maybe 10psi and finally drop back to zero and ofcourse the car would go dead. Now I looked in my chilton manual and it stated I need to drop the rear axle etc.... Any advice on this one before I start on it. Especially on what I am going to need and the safety precautions I should take? I hate working on the gas tank, especially being this is my first f-body. Thanks for your help and advice in advance

The car is a 94 lt1 z-28 6-speed.

[ConElite]

First of all, make sure the battery is completely disconnected. Then if its is possible, remove the gas from the tank. The most possible. I am hopping that you do not have the exhaust completely welded together.. it can get in the way. Other than that, just make sure man that you have that car supported in the best manner possible. Make sure your careful when u disconnect the fuel lines and once in a while touch some metal that is grounded. It keeps static from occurring. Make sure your careful when you remove the whole assembly from the tank. Good luck.... If u have any questions, post here and Ill make sure to ask my brother. I was unable to help him out due to work obligations. Asta

[Bond Hawk]

If you are handy with a dremel, you can cut an access hatch to get at the fuel pump. Be careful not to cut a fuel line.

http://www.taekwondoplus.org/z28/seal02.jpg

[MN6WS6]

If you drop the tank (aka "not monster garaging your floorboard to get to the pump" ), here is the layman's terms list:

1) Jack up car where entire back of car is as high as you can get it off the ground without the car flipping forward on it's roof
2) Remove negative battery cable
3) Purge fuel pressure (if any) from lines at schrader valve located on back of intake at top of motor. Also open fuel door and remove gas cap. Drain gas if necessary to make tank as light as possible
4) Remove right rear wheel
5) Remove swaybar
6) Remove right rear shock
7) Remove right rear lower control arm
8) Remove panhard rod and cross brace that the panhard rod mounts to
9) Remove enitre exhaust system from the connector after the catalytic convertors to the tips
9) Remove heat shields
10) Remove charcoal cannister in drivers side rear quarter panel
11) Remove tank

There's a lot of little details in between the lines that I think you can figure out, like "support rearend before you remove shock as it is the only thing keeping the rearend from severing your leg while you scream for help" It's a hella job, but better than paying $1000 to the dealer for them to do it. I did mine in about 4 hours, but I removed a bunch of steps. My steps were:

1) Back car up on ramps
2) Loosen fuel lines and spray 40 PSI of fuel all over yourself and the underside of the car because you're too lazy to get out from under the car and use the schrader valve
3) Cut off exhaust system and extinguish fire since the sparks caught the fuel on fire that was spread all over God's creation
4) Remove tank
5) Cuss GM for only putting plastic tanks in the 01-02 f-body's

[94LT1Z28]

okay, I know I probably shouldn;t do this, but I am going to anyway. The pic of the "cutout" in the rear trunk area is good, but how deep are the fuel lines? I cannot tell from thet picture. I have a guard for my dremel that I can set for grinding depth and I need to have an idea of how deep I should set it. Thanks for the input.

[MN6WS6]

I believe it is about an inch clearance. The part where you cut out is higher than the surrounding ridges, so if you set the depth to 1/4 inch you should have no problems. I've known guys to cut it with an unguarded air-powered cutoff wheel, so you should have no problems at all.

[94LT1Z28]

Hey mn6ws6, lol anyway I can get in touch with you, lol. I live in West Mobile. HaHaHa

[94LT1Z28]

another question, I was thinking about filling the tank with water once I drained it. Should I fill it with water, drain it, and repeat the draining process, or should I only need to do it once? Thanks in advance for the input as always.

[MN6WS6]

Why would you fill it with water? You're not going to be welding on it.

[94LT1Z28]

I ended up playing monster garage, and suprisingly, it took a total of about 45 minutes. The car runs great now. Thanks for all of the help and advice.

[Ken(Bone Breakin Chevy)]

man am i jealous. if i had a dremel to do that i would have. ive been at it for days. thats because i broke a strap stud and had to cut the strap so i had to order them. so i pretty much do a lil hear and there. its to be put back together. my pump is in but i dont want to fill and test before i get it straped up.

[MN6WS6]

I got 4 words:

Big Friggin Wire Tie



Just kidding. Yeah I'd wait on that strap too.

[94LT1Z28]

In the next couple of days, I will try to post a how to article on doing the dremel cut with pics. Even if you do not have any of the tools, It will not cost much to buy them. I have seen a craftsman dremel for as little as $30. The only other tools needed for the cut were a ruler, an 8mm socket, and a fuel line disconnect tool. Hopefully this experience will help someone next time, lol.

[Ken(Bone Breakin Chevy)]

that will def help. if i have to do it again, im guessing i will if ive already done it at 37k, i will do it that way.how big of an opening did you make?

[94LT1Z28]

the hole I cut was approximately 12 inches long by 7 inches wide. Not very big and easy to cover with sheet metal. I will post some pics after I get the piece of sheet metal and bolt it back in.