Has anybody suffered from an overheated fuel pump before?I think this is my problem.

The car runs and idles perfectly most of the time. Then out of the blue the car won't idle at all. It will stall and I usually can't even get it to start again. I'll leave it sit for a couple of hours and it will run fine. I finally put the correlation together that it was happening most frequently when I was under 1/4 tank of gas. However, it has happened even at 1/2 of a tank.

Has anybody out there experienced the same problem? Are there any known problems with the FBodys or fuel pumps that have problems in general?

I am running the Walbro 255 liter/hr unit.
The car is a 2000 SS w/ full bolt ons. It has heads and a 224/224 cam.

 

My Racetronix fuel pump came with all new power wires, so I would guess you would need the wireset Walbro also sells.

 

This is the EXACT Problem that has happened to me in the past few days. Also using a Walbro 255 unit. Eastside installed mine, and i know they mentioned they had to adjust the wiring to accommodate it. It's pissing me off, was out all day and i barley made it home cause everytime i came to a light it would die and wouldn't want to start. Thought it was a lack of vacuum but i'm sure it's the pump. Let me know what you find out.

 

Did they say what needed rewired?
Because I just replaced the pump. I really don't know what I should rewire. I'll look and see if I can find any info from the manufacturer.

Mssingkid - How much fuel did you have at the time it acted up? How long had you been driving?

 

3/4 of a tank. It started acting up on Sat, i had been driving just about 8-10 hours non-stop. I was cruizing in 6th, and when i went to get off the exit, the car idled really low, then died. After a few try's it turned over, but any time i gave it gas it felt like it wasn't getting fuel, sputtering and very little throttle responce. I Drove to work today(10mins away) and she felt fine, so i'm convinced that it's an issue with the pump or the fuel filter. Grr.. alway soemthing.

 

We definately have the exact same problem. When it dies it seems like it almost has dead pedal. I even changed my TPS to make sure it wasn't the culprit. I am convinced it's something wrong with the fuel pump, I just need to figure out what.

 

my 94 did the same thing to me, it has the same walbro 255. I thought it was because I Was running ~70-80 psi of fuel pressure though lol.. I haven't lowered it to test again yet, I just let it sit.

 

I really don't feel like replacing the pump, but i fear that'll be the only way to fix the issue.

 

There is a hotwire kit that runs a heavy gauge wire from the alt to the pump. $59.99 The pump draws more power than the stock one which the stock wiring can not handle. It sounds like the damage may have been done to the pump already if it is continuing to get worse.

Nate

 

I'm certainly willing to give that a try, but I did not see that listed on your web site. Can you post up a link?

 

I know i should search , but will the hotwire kit work with 98 model year cars??

 

Same issue just occured today with my 02 SS with walbro 255. I assumed fuel pump but have not put a fp gauge on it yet.

I modified the pump bucket to install it I'm pretty sure this is allowing the pump to get uncoverd with fuel causing the over heat and damage.

 

I just installed the Full Throttle Walbro setup (similar to Racetronix) and the upgraded wiring harness that I got thru Nate.

Of course, with the setup there is no need for cutting of the fuel bucket as it retains the factory jet pump feature. The wiring harness is PnP. I now have around 61# pressure at idle (up from factory 58#). No hesitation/stalling/dying issues at all.

The Full Throttle setup is very similar to the Racetronix but less expensive at $135 for the pump and $59.99 for wiring harness. Biggest difference I can see betwen the two ( I have Racetronix in my one T/A & FT pump in the other) is that the FT pump does not have the anodized sleeve for the pump as the Racetronix does. This was no big deal to me as I have many contacts with machine shops and had one custom made for free (all this does is makes the pump fit better in the factory location vs. the rubber ring that is included with the FT pump).

Both setups use the exact same Walbro pump and have the jet pump feature.

Wiring harness is MUCH better than stock wiring and includes HD relay, fuse, and take-off connector for Boost-a-pumps if you use one. Wiring install is straightforward but you must either have the tank dropped, or the trap door method done to access the top of the fuel bucket when installed in the tank as the short wiring harness section plugs in between the fuel bucket connector and factory harness connector. If you have the tank installed, but the trap door done - it is possible to run the main harness wire up behind the tank and the car to get it up on top of tank to plug into short harness - but as I stated before - you will need acces to the top of the fuel bucket to install the short section of harness.

I would recommend even installing the upgraded wiring harness with the stock pump setup.

-Jay-

 

Thanks. I'm going to get ahold of Nasty N8 and get one of those wiring kits asap.

 

Thx for the Info. I'm going to hook up a Fuel Pressure gauge and see what she reads @ the rails. I notice the car doesn't have the same responce at all now, so i'm sure the pump is on it's way out. Looks like i'll definatly be purchasing the pump/wiring kit from Nate.

 

I put on the hotwire kit. I am still experiencing the same problem at idle. At this point, the only thing I can think of is that the pump has been damaged. I will replace it and see what happens. If that doesn't work, I have no idea what to do.

 

No offense but you basically just threw money at something that was in a way common sense that it wasn't going to fix your problem. There is plenty of voltage to run that pump at a sitting idle. Why would an upgraded harness make any difference. I think whoever sold it to you should have been nice enough to point that out.

I had a Walbro that I bought back in 2003 and have been running it up until about 4 months ago when it finally went out on me and that thing worked FLAWLESSLY! I was running WITHOUT the stock fuel bucket and WITHOUT any kinda wiring harness upgrades etc and that thing worked perfect for the last 4 years.

Personally I think all this crap about wiring harnesses and needing this and that just to get the pump to work is all bullshit just so someone can make more money because the pumps that walbro was putting out back then didn't have any problems. It seems like all these new pumps are garbage. These pumps are supposed to be stock replacements. They don't say "this pump will only work if you buy a better harness or make all kinds of modifications. Now I can understand that the pump might run better if it has an upgraded harness or whatever, but in no way should there be an issue with this crap about the pump dying when there is less than a 1/4 tank of gas in the car just because of a wiring harness. Also that is NOT caused lack of using the stock bucket either, I know from personal experience. Think about it, why would a better harness or using the fuel bucket have anything to do with the pump dying while the car is sitting perfectly still at idle? You could take the same pump and put it in a bucket full of gas and when connected that pump should work no matter what, unless it's defective. If the pump is running and it's submerged in gas, then it should be pumping, PERIOD.

 

Maybe you're right. But you in no way addressed the root cause. The point is I have no idea why my pump failed. Maybe it overheated or maybe the factory wiring couldn't support the amperage requirement at WOT. The first time it ever happened to me was in the staging lanes at the track after a few passes.
What I do know is that a lot of people have this same problem and I can't find anybody with a proven solution. So I have to start eliminating possible failure modes until my car will run. PERIOD.

 

I understand. Perhaps you have a defective pump? Have you tried replacing the pump? How old is the pump? Your sure it's a genuine Walbro pump, has the Walbro branding on the side?

I only ask because I had this same problem with a pump that I bought a month ago off ebay that I was told was a Walbro pump, I never actually looked for the Walbro branding when I installed the pump as I assumed it was a Walbro. I started having the same problems as you, just as you read in my thread that you posted in. Well when I removed the pump I found out that it was in fact NOT a genuine Walbro pump, but it turned out to be one of those "LIKE WALBRO" type pumps I ended up ordered a genuine Walbro pump from summit which I installed yesterday and I drove it around yesterday but I still have a 1/2 tank in my car so I am gonna report back this weekend after I drive the car out of gas to see if this cured the problem.

 

I have a 255lph pump. I think it might be a Granatelli, but I don't remember, since it was years ago when I had the STS installed.
I can drive for about 2 hours, and then my fuel pressure goes away, the Fuel Trims go way positive, and I am screwed.
The FPR is new, so I have confidence in it.
I changed the fuel filter, although it only had about 5k miles on it.
The pump only has about 10-15k on it.
If I let the car set overnight, it will run another 2 hours.
If I check the pressure immediately after it fails, it is very low.
I have a Hypertech fuel pressure gauge that attaches to the Schraeder valve and sits in the engine compartment. I don't have a permanent gauge mounted inside the car.
Is my only option to replace the pump? I hate to do it, but if I have to, then so be it. I am in the middle of doing my tune, and it is interfering big time. Plus I can't make it to the track until it is fixed, because it is so unreliable.