Fueling & Injection - 1998 Fbody Fuel Pump Regulator questions




fstr n u
04-22-2012, 07:50 PM
I have a 1998 LS1 (chassis) Camaro with an LS2 402ci rear mount STS turbo setup....and a Racetronix in tank fuel pump replacement (from stock).

My Racetronix Fuel Pump in the car with the ignition "ON" and running runs in "High" mode...whereby it seems to pressurize or prime the fuel system...but never "kick down".

The fuel pump is noisy:

http://www.youtube.com/watch?v=92UCLtgjZ_o

I have just cut an access panel in the rear of my car and i don't see any obvious kinks or problems.

http://i192.photobucket.com/albums/z226/ryanbaliski/IMG_3902.jpg

http://i192.photobucket.com/albums/z226/ryanbaliski/IMG_3903.jpg

http://i192.photobucket.com/albums/z226/ryanbaliski/IMG_3904.jpg

http://i192.photobucket.com/albums/z226/ryanbaliski/IMG_3907.jpg


fstr n u
04-22-2012, 07:52 PM
I am thinking the "in tank" fuel pump regulator may be bad. I am not sure how to test it...and i also can't seem to find anyone who can find me a part number without wanting to sell me a whole fuel pump assembly.

Does anyone know a GM part number for the little black plastic fuel pump regulator with the brass nipple/line ....or know of where to get a replacement from?

If this does not fix the problem i am having with a fuel pump (Racetronix) that is running noisy at all times with no obvious restrictions...i am at a loss.

01ssreda4
04-23-2012, 02:22 AM
Where's your bucket? I'd try to find an assembly at a junkyard if the regulator is in question.


fstr n u
04-26-2012, 12:07 AM
What bucket?

From what i understand the 98's and earlier are different from the 99's and newer. What you see is what was stock except for the racetronix pump in place of the stock one in the assembly.

Still looking for assistance.

fstr n u
04-26-2012, 12:37 AM
Here's a pic of another 98 Camaro with no bucket, not sure if that's a 99 thing and newer?:

http://i192.photobucket.com/albums/z226/ryanbaliski/May%202011%20Camaro%20rebuild%20starts/1998camarofuelpumpassemblylarge.jpg

fstr n u
04-26-2012, 12:39 AM
I just found the name for the part i want to start with: Fuel Pressure Regulator...not fuel pump regulator. Here's pic of the part:

http://cf.mp-cdn.net/2c/74/a46c142971af252c85dc221a2a86.jpg

ryle
04-26-2012, 03:50 AM
I have a 98 and they did have a bucket stock. They are not the same as a 99+ but they did have one. I don't have one anymore because I am running a twin 255 setup at the moment. I found this on Autozone.com http://www.autozone.com/autozone/parts/Gp-Sorensen-Fuel-Pressure-Regulator/1998-Pontiac-Firebird/_/N-j9vxvZ8vd1h?itemIdentifier=221962_0_0_

Lonnies Performance
04-26-2012, 06:56 PM
You can replace the metal regulator part, but most of the time, it is the plastic part of the regulator (the part connected to the metal tube) that deforms over time & leaks off pressure.

98Camarod
04-27-2012, 04:45 AM
I think I might have an extra one laying around if you need it. Just let me know.

fstr n u
04-27-2012, 03:08 PM
I replaced my stock regulator and the problem is still there.

Now to find another reason why this pump isn't working right.

Mr. Fuel Pump
04-27-2012, 05:34 PM
The Walbro pumps are inherently noisy, I don't think your pump sounds out of the norm, but some Walbro's are noisier than others, and then get real noisy if the are starved of fuel or hot or getting ready to die. Your filter sock could be clogged making the pump work harder which could make it louder than normal. Did you install the pump with a sleeve around it to lessen structure-born noise? Are you seeing any performance issues, or is it just 'noisy'?

01ssreda4
04-28-2012, 06:15 AM
I replaced my stock regulator and the problem is still there.

Now to find another reason why this pump isn't working right.

You're question is being answered you aren't listening.

fstr n u
05-03-2012, 08:57 PM
The sock that came with the racetronix pump looks good, no apparent obstructions. I will try and find a place to find a new sock and see if that makes any difference, though my Racetronix one only has less than 1000kms on it.

Does anyone have a pic of a shield or bucket for the 98's specifically?

I haven't been able to test out if there are performance issues, as there is an ECU limiter of 3500rpms in my neutral and 2nd gear. Couple that with the fact i'm on a base STS tune for my new LS2 motor, and my turbo is bleeding off boost at 4 psi.

fstr n u
05-03-2012, 09:05 PM
01ssreda4 - i am a fish out of water with this problem. I have very basic mechanical skills and i'm learning as i go, and thanks to everyone who helps out on these forums, as i have learned a ton!

In the city where i live, there is a garage that specializes in fuel systems, and yet when i took it to them, they told me that my fuel lines and brass t connecter after the fuel filter couldn't possibly be stock as the 90 degree bended fuel line has a weird flare fitting on it.

Turns out that all my componentry is stock under the car (except for the racetronix pump and associated wiring)...which has me concerned now because they couldn't help me out. Why i am concerned is that i have just had professionally trained individuals looking at my car and they didn't know what they were looking at.

We don't have a large aftermarket group of mechanics/technicians that can help out with stuff like this (i am now learning) and i am now stuck.

So bear with me and my hope is that with a bit of time and suggestions, i'll get this problem licked.

98Camarod
05-04-2012, 05:37 AM
So what exactly are you saying the problem is?

It's going to be loud. If your saying that the pump stays on when you have it koeo. I think it's only supposed to prime for 3 mins then completely stop running. Or are you concerned about fuel pressure?

You have a turbo, so you should have a boost referenced regulator. I'm sure you don't since you are talking about the stock tee fitting.

fstr n u
05-04-2012, 03:31 PM
The current problem is that with just the ignition on...the fuel pump runs continuously and never shuts down (constant priming). The fuel pressure never exceeds 62 psi.

We are trying to figure out what would cause the fuel pump to continue running and not simply "prime and then shut down".

I have never heard of a boost reference fuel regulator...so i will check into that too.

mike171562
05-04-2012, 04:12 PM
My 98 had no bucket it was more like a plastic case that held the pump, the walbro wouldnt fit in it so i ditched it and just zip-tied it

MY99TAWS6
05-05-2012, 04:34 AM
here are some pics if you scroll down showing my boost referenced regulator and my big fuel filter on the front of the fuel rail .
Serious lines serious fuel system. Lonnies all the way. I dont' think a single racetronix is going to cut it anyway FASTRNU not for long with what you have happening now the bigger turbo,408.
So maybe just man up..JOKING and get a nice dual setup from lonnie. no factory reg, no wimpy filter ,big lines,etc. Do it once do it right you have gone this far. Might as well go the rest of the way. And as said boost referenced reg is what you want in a turbo car. not factory reg. But guess have seen that setup with just racetronix used at lower boosts and you are at lower boost at 4psi thats baby boost. Still think you must have boost leak should hit gate in higher gears for sure. Like third. You said the limiter is in neutral and second so go into third and if its still at 4psi you have boost leak somewhere or dud turbo. Or maybe terrible backpressure but the sts has no muffler right. Too restricted an exhaust will severely limit boost. Buddy with sts had clogged cat and it totally killed his power he lost over 100 hp or more. We took out cat and the thing was rocketship again. Are you running cats ,are they clogged>? high mileage.
I wish you could hear my setup and maybe you can if you come thru Kelowna and I have car here. I really don't think my pump is that loud. But i also have mega stereo in the car.
Cutout is not on there right now either between stereo ,cutout , turbo and blow off noises not likely to hear fuel pump.

LS1TA_956
05-05-2012, 04:49 AM
The ws6 store sells regulators for our 98 model fbodys

Brad Campbell
05-05-2012, 06:56 AM
So your only problem with the fuel pump is that it stays on all the time with the ignition switch?

Is it possible that whoever installed it performed a rewire with the suggested larger gauge wire, but tied it to the ignition, and not a relay with the current ecu fuel pump trigger?

fstr n u
05-05-2012, 08:41 AM
1. So your only problem with the fuel pump is that it stays on all the time with the ignition switch?

Answer: Yes, and the exact same thing when the car is running.

2. Is it possible that whoever installed it performed a rewire with the suggested larger gauge wire, but tied it to the ignition, and not a relay with the current ecu fuel pump trigger?

Answer: Maybe. Does anyone know where the relay is for the ECU Fuel Pump Trigger?

3. Regarding boost leak

Answers: I think i'm going to have to build a DIY boost leak tester once I get this fuel pump issue sorted out and see if something is leaking.

One of the local tuners was wondering if my car is producing so much air flow that it is overpowering the spring in the wastegate. So at some point we will try turning up the Turbo smart boost T and see if that allows the turbo to create more than the 4psi boost my car is currently making.

4. Regarding the Neutral and 2nd gear (3500 rpm) limiter

Answers: I have sent an email to STS to ask if they can go over the tune they mailed out to a local tuner to see if they can figure out why this limiter would affect my neutral and 2nd gears ONLY. So i will wait to hear back from them and see what their thoughts are.

Mr. Fuel Pump
05-05-2012, 04:10 PM
1. So your only problem with the fuel pump is that it stays on all the time with the ignition switch?

Answer: Yes, and the exact same thing when the car is running.

2. Is it possible that whoever installed it performed a rewire with the suggested larger gauge wire, but tied it to the ignition, and not a relay with the current ecu fuel pump trigger?

Answer: Maybe. Does anyone know where the relay is for the ECU Fuel Pump Trigger?


Your pump is supposed to stay on all the time if the engine is running. ;)

As far as ignition switched on, but engine not running, and the pump won't turn off, I agree that a rewire was performed and they didn't wire it properly. Try to get the hotwire instructions from Racetronix and see if you can figure out how to hook it up properly, or buy a new hotwire kit from Racetronix and start from scratch.