GT350 Fuel pump issues

[oneill_nolan]

My issue began after running out of fuel. I drove to work low on fuel and said I would fill up after work. I had 50 miles to E and planned on stopping at a gas station closer to my house (about 5 miles) hopped onto the freeway and got onto it a little. Suddenly the miles till E rapidly started dropping, watching it going from 50,40,30,20,10 to zero. oh sh!t. I got off at the next exit and tried to find a good spot to park up so I wasn’t on the side of the road. It started to sputter and die out, like an idiot I tried starting it a couple more times just to get out of the road. Called for help and got some gas, upon startup I noticed a check engine didn’t think much of it. Went to the gas station and filled all the way up. Starts and drives perfect, full acceleration is fine too runs like a clock, but on decel it stutters and bucks for a couple of seconds. I scanned it and found code P0087, (fuel rail pressure too low bank 1) P026 (Fuel pump a control circuit / open) P0627 (Fuel pump A control circuit / open). I’m thinking I either burnt one of the two pumps up running the tank dry or it’s one of the modules. Fuses and relays checked and ok.

Sponsored

 

[icecreamtruckz]

Pump heat from it being nearly dry is a possibility. But that’s an after problem. What would be the reason for 50 miles to disappear off the range that quick? That’s what, 2 gallons of liquid roughly? Was that a fluke and the real problem started with a dry tank, or is it related to the current issues?

The fuel pump codes both coming from one pump seem like a good start. The range thing is very odd.

 

[NGOT8R]

While it could be a faulty pump, I’d try bypassing the FPDMs before pulling the pumps.

https://www.mustang6g.com/forums/threads/suspected-bad-fuel-pump-2019-bullitt-on-e85.189945/

https://www.mustang6g.com/forums/threads/2019-bullitt-fuel-pump-driver-module-failure.201965/

 

[oneill_nolan]

Pump heat from it being nearly dry is a possibility. But that’s an after problem. What would be the reason for 50 miles to disappear off the range that quick? That’s what, 2 gallons of liquid roughly? Was that a fluke and the real problem started with a dry tank, or is it related to the current issues?

The fuel pump codes both coming from one pump seem like a good start. The range thing is very odd.

Im thinking that when I got onto it, the miles to E dynamically changed? Or there’s an issue with the sending unit? Haven’t noticed any issues with the gas gauge since.

 

[oneill_nolan]

While it could be a faulty pump, I’d try bypassing the FPDMs before pulling the pumps.

https://www.mustang6g.com/forums/threads/suspected-bad-fuel-pump-2019-bullitt-on-e85.189945/

https://www.mustang6g.com/forums/threads/2019-bullitt-fuel-pump-driver-module-failure.201965/

Unplugging the FPSM’s would just cut power to the pumps?

 

[NGOT8R]

Unplugging the FPSM’s would just cut power to the pumps?

No. I took those pics when I was stranded one day and had to make those jumper wires on the spot, in order to drive the car home.

 

[SheepDog]

Fuel pumps are consumable/Maintenace items in my opinion anyway. Just replace them

 

[JAJ]

My issue began after running out of fuel. I drove to work low on fuel and said I would fill up after work. I had 50 miles to E and planned on stopping at a gas station closer to my house (about 5 miles) hopped onto the freeway and got onto it a little. Suddenly the miles till E rapidly started dropping, watching it going from 50,40,30,20,10 to zero. oh sh!t. I got off at the next exit and tried to find a good spot to park up so I wasn’t on the side of the road. It started to sputter and die out, like an idiot I tried starting it a couple more times just to get out of the road. Called for help and got some gas, upon startup I noticed a check engine didn’t think much of it. Went to the gas station and filled all the way up. Starts and drives perfect, full acceleration is fine too runs like a clock, but on decel it stutters and bucks for a couple of seconds. I scanned it and found code P0087, (fuel rail pressure too low bank 1) P026 (Fuel pump a control circuit / open) P0627 (Fuel pump A control circuit / open). I’m thinking I either burnt one of the two pumps up running the tank dry or it’s one of the modules. Fuses and relays checked and ok.

Just in case there's any confusion, the GT350 and the GT500 have two separate fuel pumps, one on each side of the tank. Other S550's (like the GT, the Bullitt and Mach 1) have one fuel pump equipped with a siphon arrangement so it can pull fuel from both sides of the tank.

From your description, it's very possible that one of your two pumps failed. Depending on how the plumbing works back there, one dead pump might cause the car to draw fuel from only one side. It would be able to run that down fairly quickly, leaving you stranded while there's still fuel in the other side of the tank.

That kind of a failure would explain all of your DTC's, and the rapid drop in fuel level. It would also explain why the car runs fine with a full tank. The one remaining pump can run the car pretty well if it has to, with the ECU setting DTC's to let you know that something's not quite right.

 

[NGOT8R]

A couple of DW400 pumps would give you peace of mind in knowing that your pumps are new. They’re relatively cheap and easy to install.

 

[oneill_nolan]

Just in case there's any confusion, the GT350 and the GT500 have two separate fuel pumps, one on each side of the tank. Other S550's (like the GT, the Bullitt and Mach 1) have one fuel pump equipped with a siphon arrangement so it can pull fuel from both sides of the tank.

From your description, it's very possible that one of your two pumps failed. Depending on how the plumbing works back there, one dead pump might cause the car to draw fuel from only one side. It would be able to run that down fairly quickly, leaving you stranded while there's still fuel in the other side of the tank.

That kind of a failure would explain all of your DTC's, and the rapid drop in fuel level. It would also explain why the car runs fine with a full tank. The one remaining pump can run the car pretty well if it has to, with the ECU setting DTC's to let you know that something's not quite right.

I thought both pumps were on the same basket on the drivers side, and used the venture system to draw fuel from the passenger tank? If that’s the case then everything makes sense.

 

[oneill_nolan]

A couple of DW400 pumps would give you peace of mind in knowing that your pumps are new. They’re relatively cheap and easy to install.

Retrofit into the OE basket or is it the whole assembly? I was looking into those a bit.

 

[NGOT8R]

Retrofit into the OE basket or is it the whole assembly? I was looking into those a bit.

I retrofit mine into the OE basket.

 

[oneill_nolan]

Fuel pumps are consumable/Maintenace items in my opinion anyway. Just replace them

hell everything is consumable at this point

 

[oneill_nolan]

I retrofit mine into the OE basket.

Was it a pain in the ass? Guessing I’m going to have to trim some of the basket for the larger pumps. Wonder if the stock pump modules would work?

 

[NGOT8R]

Was it a pain in the ass? Guessing I’m going to have to trim some of the basket for the larger pumps. Wonder if the stock pump modules would work?

No it wasn’t. It was fairly simple and I was very analytical about it I even modified my basket (see green highlighted area) to clear my ear clamp pliers which are used to clamp the lines onto the fittings.

In the first pic you can see where I cut the pump holder and rounded the corners. I did some other trimming as well using a Dremel. Not hard at all. Once you start, you’ll see exactly where you need to take away material to make the pump fit properly. All of the rounding of corners and basket modification probably were t necessary, but my OCD made me do it that way, lol.

Sponsored