I'm getting a 251 code every now and then when I'm just driving, but almost always it will come on after towing something. From 8000 lbs to 2000 lbs makes no difference. It will come on after driving with the trailer for an hour or so, or after pulling the trailer a couple miles at 60mph then shutting down. Upon restart I'll have the code.
I know this is low fuel pressure related, but I've been having this issue on both my diesel side (7psi idle, 4psi running) and my VO side (fass pump 10-13psi and separate filters, lines, etc). I had thought that possibly the IP inlet screen was getting dirty and restricting flow, so pressure would read on the gauge (which was in line, roughly 8" from IP) but it wouldn't be getting any inside the IP. I pulled it apart yesterday and the screen was awful dirty. Blew it out, welded up a 1/4" ID fitting for the IP inlet, then reassembled.
It ran a bit better, but still didn't have much power when I hooked up to my small utility trailer and threw the code again when I went to start it after I turned it off for 15-20 minutes.
I've changed optical sensors and results are the same between them. Fuel is clear as well.
Thoughts?
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-1996 GMC 2500, F vin, 274k, Gold/Tan, Ex/LB
10psi TM, VDO Boost & EGT gauges, Heat sheilded custom CAI, New Starter, New Batteries, New Crank Pulley, New Harmonic Balancer, Bully Dog 3" Downpipe & 4" Full Exhaust, New 93' HO LP, New DTech Bumper Mounted PMD, Marine Injectors, Pensicola IP, MB Motoring WHeels, 285/75s, WVO system.
-1997 BMW M3 Sedan Silver/Black 113K Modded
-1996 BMW 328is Blue/Gray 170k Modded
I know this is low fuel pressure related, but I've been having this issue on both my diesel side (7psi idle, 4psi running) and my VO side (fass pump 10-13psi and separate filters, lines, etc). I had thought that possibly the IP inlet screen was getting dirty and restricting flow, so pressure would read on the gauge (which was in line, roughly 8" from IP) but it wouldn't be getting any inside the IP. I pulled it apart yesterday and the screen was awful dirty. Blew it out, welded up a 1/4" ID fitting for the IP inlet, then reassembled.
It ran a bit better, but still didn't have much power when I hooked up to my small utility trailer and threw the code again when I went to start it after I turned it off for 15-20 minutes.
I've changed optical sensors and results are the same between them. Fuel is clear as well.
Thoughts?
____________________
-1996 GMC 2500, F vin, 274k, Gold/Tan, Ex/LB
10psi TM, VDO Boost & EGT gauges, Heat sheilded custom CAI, New Starter, New Batteries, New Crank Pulley, New Harmonic Balancer, Bully Dog 3" Downpipe & 4" Full Exhaust, New 93' HO LP, New DTech Bumper Mounted PMD, Marine Injectors, Pensicola IP, MB Motoring WHeels, 285/75s, WVO system.
-1997 BMW M3 Sedan Silver/Black 113K Modded
-1996 BMW 328is Blue/Gray 170k Modded
