tbird31

iTrader: (22)

First off, my car is a swap car. The first time I drove it was actually exactly a year from Thursday. (wicked) But since completing the car I've run through 2 Walbro 255 pumps and I'm thinking the third one is about to be on it's way out.

Symptoms are that the fuel pressure starts to drop little by little, then it gets down to about 20psi and then starts fluctuating between 10 and 30. Then either it will die or I'll pull over before it does. I haven't run the tank lower then about 1/4th since the first one went out just because I thought that's what did it. Weird thing is that I can pull over and let it cool for about 15-20 minutes and roll on my way after that. So obviously somethings heating up, that's my guess at least.

About 6 months ago I was on the way to Rockingham Dragway, which is about an hour and 15 minutes away from where I live. After about an hour, 15 minute out from the dragway it started fluctuating and going haywire, so I pulled over and it died before I parked. I sat around for 20ish minutes to let it cool, drove the rest of the way to Rockingham, let it sit for an hour and then made about 5 or 6, 1/4 mile runs with the car. Sat it for 20 minutes and drove all the way home without a problem.

Then last night, I drove it home to Mooresville, about a 45 minute to hour ride with a good bit of traffic. I was kind of irritated at the amount of traffic, it was stop go for a little bit but wasn't too bad, and it's not 100* out so I wasn't really worried about it overheating. Sure enough though, 5 minutes from the house it starts going nuts, pull over, sit for 5-10 minutes and drive it the rest of the way. Parked in the driveway for 4 hours and then drove it the 45 minutes home without a hiccup...WTF!

Another weird thing is though that I can drive the car all day long around town, and I drive the **** out of my car, and it does fine. It's like a sporadic error. Irritating as hell.

I'm freaking confused as ****. I really don't want to eat another $150 pump, I'd like to find the problem and fix it. Any suggestions?

chevyz2801

iTrader: (20)

I would look for a restriction somewhere. Is the fuel system stock except the pump?

tbird31

iTrader: (22)

The lines from the fender well back to the pump are stock yes, but the injectors/regulator/pump are all upgraded obviously to handle the LT1.

I need to change the fuel filter but I for some reason don't see that being the problem.

Has anyone ever run stainless steel braided lines for their fuel lines? What size if so?

chevyz2801

iTrader: (20)

so this is a return system what size is your return

tbird31

iTrader: (22)

The car is a 1995 Firebird, it was a 3.4 liter V6, but I swapped in a built 355ci LT1. I cut the fuel lines to length for them to connect to the fuel rail, and then just dropped in a Walbro 255 pump, which is a plug and play.

I've been wondering if there's a difference in the amount of power sent to the fuel pump on the V6 and the V8 cars. I'm pretty sure I checked and it's the same but I'm not 100% sure.

If there was a difference in power then it might explain why they keep burning up, I'd assume it's not getting enough power so it's having to work harder, but then again I'd assume if it was that I'd have a lack of fuel pressure...

99_SS_LS1

iTrader: (4)

I would check your power and ground wires. Don't ohm them though, instead look for voltage drop between the power source and fuel pump connector, and then the same from fuel pump connector to ground.

I'd bet you have high resistance in one of those circuits.

chevyz2801

iTrader: (20)

you can try the hotwire kit. Do you have a line that sends the fuel from the reg at the rail back to the tank, im not that familiar with a 95 but my car is a 01 and doesn't have a return line so i will be adding one soon when i do my duel intank setup.

tbird31

iTrader: (22)

Yes, it's the stock return system.

I'm going to look into the hotwire kit, I'm curious if it'd do anything.

C5Fire

Make sure your tank is venting properly. If you drive the car for 20 min, stop with the car running and pull the gas cap. If you hear air rush in then your tank is not venting and that is your issue.

salemetro

iTrader: (5)

I would almost guarantee that it is due to either 2 small of a supply/ground, or weak ground connections....that just seems to be too weird that they are going out that often. Have you checked for signs of an "over-heating" ground wire??

rpturbo

iTrader: (47)

Definitely sounds like a grounding issue. I bet it's using the fuel line or the pump case somewhere as a ground and the pump is struggling when it gets warm to keep the ground. A hot wire kit is the way to go to make sure you keep good high voltage at the pump, and it should also fix the ground issue.

Old Geezer

iTrader: (3)

being this is a "hotrod", did you remove the smog stuff, and plug off some unused lines??
As C5Fire mentioned, the tank vent may be the cause. A vacuum condition in the tank will cause the fuel to boil, and create "steam", if you will, at the pump inlet.[Bubbles in the fuel]. Gas boils at about 135*F..Wose when it's a "winter blend". This is a fatal condition AKA: Cavitation.
What is the part number on the pump?

max_ta

95 TA here every time I get gas it sucks in air is this not normal, did you change fuel lines with the swap, pretty sure there is a differance in lines(supply and return) from v6 to v8 sounds like a vapor lock to me

V6 Bird

iTrader: (15)

Is this pump installed inside the tank with a V8 Tank or the stock V6 tank? Are you gravity feeding the pump if its installed as an external/inline pump? What it sounds like you are experiencing is Pump Cavitation. And when it isnt able to keep the pump cool with the fuel from the tank, it builds heat. This is what they describe as vapor lock as well on the pump.

da98transam

iTrader: (5)

i have the same problem but i have not burned mine up yet but when mine shuts off i can add cold fuel to it and go on my way.i have a hot wire kit on mine did not help.i am going to put a vett fuel filter on my car it has a return line on it and see if will stop my issue i will let you know but it you find out anything let me know thanks

jgb454ss

I read somewhere that there was a bad batch of walboro pumps circulating the net. Where are u getting urs from.

tbird31

iTrader: (22)

I put a hot wire kit on it about 2 years ago now, and it solved the problem.

ZexGX

iTrader: (28)

Only a new fuel pump will fix your issue if adding cold gas to it makes it work. Sounds like the pump is worn out and overheating.