Uh Oh Truck Sputtering On Cold Start
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Joined: Feb 2005
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Uh Oh Truck Sputtering On Cold Start
On the first start of the day or when I go home from work, 11 hours after I get there, my truck sputters for about 3 seconds really nasty unless I catch it quick with some throttle. At first this would only do it on the front tank, starting about 3 months ago, now it does it on both. Once the truck is running after that 3-5 second period of roughness, it doesn't lack any power and you can't tell there's an issue while driving.
This leads me to belive that i'm slowly bleeding off fuel pressure in the fuel rail while the truck sits for an extended period of time.
What keeps the fuel rail pressurized? Is there a check valve of some sort? Does the fuel pressure regulator on the fuel rail act as a check valve to keep the fuel rail pressurized while the truck sits?
I replaced the fuel pressure regulator with a genuine FoMoCo one about two years ago. It wasn't sputtering though... it was running too rich and had a slight off idle miss. It seemed to have fixed that issue no problem. I have never experienced this problem before (3 months ago) with this truck. Truck throws no codes and no check engine light.
1995 F150 SWB 300EFI / 5 Speed
This leads me to belive that i'm slowly bleeding off fuel pressure in the fuel rail while the truck sits for an extended period of time.
What keeps the fuel rail pressurized? Is there a check valve of some sort? Does the fuel pressure regulator on the fuel rail act as a check valve to keep the fuel rail pressurized while the truck sits?
I replaced the fuel pressure regulator with a genuine FoMoCo one about two years ago. It wasn't sputtering though... it was running too rich and had a slight off idle miss. It seemed to have fixed that issue no problem. I have never experienced this problem before (3 months ago) with this truck. Truck throws no codes and no check engine light.
1995 F150 SWB 300EFI / 5 Speed
Mountain Pass
Joined: Jan 2005
Posts: 157
Likes: 16
From: Everett
Put a fuel pressure guage on the shraedar valve that sits on the end of the fuel rail. That will give you a good indication of your fuel pressure, and if this is actually your issue. From what I understand though, the ball type valve that switches between tanks may be failing. It is possible that it is opening on one tank all the way and then when you switch over, it isn't opening on the other tank all the way. This could play with fuel pressure as well.
