I've been having fuel pump problems on and off for the last few years now and I am not sure if I am just unlucky with bad pumps or if there is another problem somewhere.

First off, my OEM pump died on the track. It started cutting out when turning left, then cutting out almost all the time. This was a known problem, so I replaced it with a Walboro.

This second pump didn't last very long, but eventually went and the diagnosis was a bad regulator. Ok, no problem. RMA'ed and got a new one.

Third pump -- another Walboro -- lasted for a while but started getting noisier and noisier, then the same problems as my initial pump came back. It started cutting out at 8k. The more I drove it, the more it cut out. 7k... 6k... all the way down.

Fourth pump -- Aeromotive (340 I believe?) -- just went in in the spring. Things started off pretty bad. I couldn't even start the car. It would crank about 14 times, sometimes start if the battery didn't die, choke, then die right away. On the second start, it would struggle a bit and be fine. This would happen consistently if the car went cold. Eventually I uninstalled my MM tune and things seems ok for a while. Reflashed my tune, and a few days later the car started behaving like my last few pumps. (Die at 8...7...6...etc). Uninstalled the tune again, this time nothing changed. Same problem remains.

Troubleshooting I've done on this pump:
- Cleared the ECU several times
- Replaced the fuel pump resistor with a brand new OEM unit.
- My voltage readings are as follows:
--- Before the resistor: ~14v
--- After the resistor: ~11v
--- At the fuel pump: ~10v (not 100% if I have a good ground here. I tried the seatbelt bolt and the black wire in that area and both showed 10v.)

I don't know if these are correct or not. My original resistor was reading 10v after the resistor. Tested a friend's car and his read ~13 in and ~11 out so I thought mine may have been bad, but even with the new one the same problems remain. Not sure why his dropped 2v (which I think is what it's supposed to be at) but my new one dropped it 3v? Defective new resistor?

If anyone has any ideas on what I should check next, please advise. I'm really not sure where to go from here.

PS: I need to plug in a big thumbs up to Charles @ Black Halo Racing here. He RMA'ed all defective pumps and continued to provide support over almost 2 years on this issue, including over my winter storage periods and he is still helping out on this problem (though I'm open to hearing everyone at this point as my car is pretty much unusable right now).

Thanks in advance!

 

So, the issue only occurs when you reflash with the MM tune?

 

Fuel pressure for sure....

you might want to check the wiring between the lid of the assembly and the actual pump connections as well...

 

get the 09 pump assembley also--its proven and it works. On a na engine you will not need more fuel than it can provide.
Also like Dan has said--you have resistance somewhere. You may have a bad ground ( Some are under the seats, under the carpet) or the resistor may be bad.
14volts to the resistor?
You can bypass the resistor to see if that makes a difference. Instructions for that are in the forum--somewhere.

 

No, it occurs on the OEM tune as well (which I am staying on until this is solved just to be safe)

Yea pulling the pump is something I'd like to keep for last on my list. I was hoping someone would be able to tell me if my voltage readings are normal or not.

This time I didn't do the pump myself because the issue happened over the winter and my workspace isn't insulated. I have no doubts at all that the shop that put it in may have screwed something up. But since pulling it is a pain, and I don't have a fuel pump tool, I'm hoping to keep that for last.

Yea another "new pump" is also a last resort. I'd be glad to check each ground though I'm not sure where the relevant grounds are for the fuel pump.

Yes 14v in... alternator puts out around 14v, as I understand it the goal of the resistor is to drop that down to something the fuel pump can handle.

I'll look into that bypass but the resistor is brand new so...

 

After more searching, I am thinking that it may be a dirty fuel sock.

 

So overall it looks like it's down to one of these problems.

- Fuel relay issue - need to benchtest
- Clogged fuel sock (dinky *** fuel filter that we have which is built into the pump assembly)
- Siphon assembly not picking up fuel from the main tank into the bucket fast enough and starving the pump
- Regulator in the OEM assembly not properly throttling the amount of fuel that the aftermarket pumps are putting out; fuel pump emptying the bucket too quickly and starving itself.

My plugs were wet the last time I pulled them, so the last option might be correct. If that's the case I might just get an 09 assembly and get rid of this one.

 

I bought an entire assembly, and just got a jobber tool in the mail the other day so i might be able to spread some light. my car was having powerloss with hard throttle, especially at end of trips, and was making a lot of noise and dying at all speeds before i parked it.

FYI entire drop in assembly was like 230 after shipping and tax at rock auto.

 

Looks like Rock Auto sells two aftermarket replacement pumps... AIRTEX and CARTER brand.

Which one did you get? Anyone else try either of these pumps? Any ideas what brand of pump is actually in there?

 

At this point I am ready to just get an OEM pump from the junker then strip and sell the car and buy something else. I am fed up with this issue and I don't even know if the pump is actually the problem or not, the dealer is incompetent at dealing with the issue because there are so many aftermarket parts in there, and nobody around here has any knowledge of this car.

Wasted almost 3 years and over $1000 on parts/labour and still having fuel problems after 4 pumps (going on 5 I guess) and now it looks like my only solutions are to keep spending money on replacement parts hoping that the problem gets solved, and even if I do that, the solution is either 1) another OEM pump that will fail on the track or 2) mangle my OEM fuel system and go to an S II pump that still might not solve the problem but leaves me with a mangled hack and no easy way to go back to OEM.

This car is seriously pissing me off right now.

 

Do you ever run the car extremely low on fuel? When the fuel level warning light comes on, does a fill take about 13 gallons? Is the starvation issue worse in LH turns compared to RH ones? Conditions that cause the pump to run dry may shorten lifetime considerably.

 

Car is on a nearly full tank right now.

The starvation issue is for the OEM pump, which I already killed. My current issue is that pump #4 (Aeromotive 340) is still failing after I had 2 Walboro 255 fail as well.

I'm not saying that there isn't possibly another cause that the pump is starving -- maybe the siphon is not working or the filter is clogged. I'll check the filter as soon as I can get my hands on a fuel pump tool but I have no idea how to check the siphon and I bet you the dealer doesn't either.

 

I'm trying to get at, though the tank is full now, the pump may be getting damaged by running dry when it is not. One clue wrt the siphon is that a fill from warning light on isn't taking 13 gallons but significantly less - the rest being trapped on the other side of the hump. I have a vague memory that there was a recall on some VIN #'s for fuel tank issues related to this:

"Manufactured between: 04/10/2003 and 07/07/2005
Defect: if certain passenger vehicles are parked and the engine is operated at high rpm's for an excessive length of time, some of the parts around the exhaust system can melt and produce a variety of malfunctions. problems caused by the excessive heat build-up can range from inoperative oxygen sensor, neutral switch and back up lights, problems with the parking brakes, malfunctions of the gas gauge and/or possible fuel leaks resulting from heat damage to the fuel tank.
Consequence: fuel leakage, in the presence of an ignition source, could result in a fire."

Perhaps the fuel tank is damaged in some way ...

 

^ Good info, thanks.

I did fill up not too long ago and it was just as expensive as ever and took the normal amount of fuel. But this does help me assume that the siphon is working fine, so it was helpful.

As soon as I can find a fuel pump removal tool I am going to pull the pump. If the filter is not clogged I am just going to drop in another OEM pump and run the crap out of it.

 

i feel like i am having this same problem. it starts like a hot start but its not consistent with it being warmed up, it can be the first time i drive it. all of which started around a time when i was low on fuel. and it was worse when i was running below a quarter of a tank and then filling up it would start real hard. i checked my coils and they are fine. i tried seeing if i could burn carbon off the plugs and nothing. however some times it bogs down when i start it, and over 6 grand when its supposed to kick all the shutter valves open sometimes it feels like its bogging down. i dont have much time at all to search for this and i've asked several people and compared to my kawasaki forum a lot of people on here aren't as helpful. would any of you have any ideas? i'm thinking about swapping out a walbro just in case but its been going on for a few weeks i'm afraid i may screw something up if i don't figure it out soon.

 

What all have you done so far that leads you to think its probably the fuel pump?
Have you rented a fuel pressure tester and confirmed it being a problem?

What other maintenance have you done on your car recently?

BC.

 

Just an update for those interested.

Fuel pressure was at 15psi under load, and swapping in a new OEM pump fixed all the issues. Been running on it for a few days now and all is fine so far.

At this point my assumption is that one of the following is the cause:

- Something went wrong in the pump assembly modification, causing all 3 aftermarket pumps to die
OR
- The Walboro failures were random and the Aeromotive pump was improperly installed
OR
- All 3 pumps were unfortunately built on a Monday morning/fakes/unfortunately defective
OR
- There's more to it to make these pumps work properly in our cars

I have my doubts on all of the above, but I am sending my assembly to BHR to have them look at it and give me an answer.

Regardless of the answer, I'm not going to swap this pump again. Wasted enough time and money on this.

 

The OEM filter in the canister, and the fuel pressure regulator are the only things that were not changed between the 3 changes and was changed with the new unit...likely it has something to do with that. The Aeromotive pump is likely fine...they are good quality units. To test it you could remove the pump out like and attach it directly to the outlet nipple and test the output...that will remove the filter and the regulator from the equation

 

15 psi? that sounds horribly low... My gauge sticks at 60 psi like clockwork

 

i feel like i have the same problem. im installing a guage this week, got a oem pump in the mail to replace the walbro. subscribed

 

So i just finished the instal of my fuel pressure guage, fuel pressure stays around 58-61 psi all the way to redline but my AFR is not that steady...goes from 12.6 at 5krpm to 17.2 at 7200rpm....what else could that be?! Injectors??

 

Wow, that's really lean. I had a similar problem at one point (although it was no where near that severe) and we tracked the problem down to clogged injectors on my rear rotor. I guess it could be your MAF too but it's hard to say for certain.

17.2 is REALLY bad. Have you tried running a stock map? I would be really worried about the ping of death.

 

i believe my car has always been like that, even when i was stock because it always misfired when i was pushing it.

guess i will have to clean injectors!

since i can read my AFR with the AP, im easy on the pedal and i stay below 6k

 

Take a look at your MAF #s too... You shouldn't see anything too wonky. If you have a nice consistent MAF rate then even more reason to look at the injectors.

One other (unlikely) source is your OEM wideband but one would think it would throw a CEL... dunno.

 

Sorry to hijack the thread but quick question. My fuel pump is failing confirmed with fuel pressure readings...anyways my car is completely stock except for a catback so should i upgrade to a 255 walbro or 300 Deatsch Werks? Sounds like this may not be a good idea.
Is it easy to install a 09 fuel pump in an 05?