P0251 after fuel system replaced 03 alh

[Sidergym]

Rough idle led me to replace injection pump twice, The second time with a high-end rebuild and all the injectors. Rough idle remained so BEW lift pump installed. All of the easy stuff fuel filter thermostatic t ect. The idle feels good but the P0251 and flashing glow plug continue to come back. It's a code that says stop drivingBut there's nothing else I can fix or replace can someone please tell me what might be causing me to get this code after all this work.

 

[Dmwitty22]

I’m also currently trying to solve this issue, tomorrow I’m throwing a crank sensor at it as It only wants to start acting out on my drive home once the car is hot for the first time in the morning, unsure as to why I get an injection pump code for crank issue but my pump is newer aswell can’t believe the pump could be bad compared to what I replaced last year. If I remember tomorrow after I replace the g40 crank sensor and it works out I’ll reply back

 

[Sidergym]

I’m also currently trying to solve this issue, tomorrow I’m throwing a crank sensor at it as It only wants to start acting out on my drive home once the car is hot for the first time in the morning, unsure as to why I get an injection pump code for crank issue but my pump is newer aswell can’t believe the pump could be bad compared to what I replaced last year. If I remember tomorrow after I replace the g40 crank sensor and it works out I’ll reply back

A new crank sensor fixed my P0251 issue.

 

[Dmwitty22]

So today I slapped a new crank sensor in, it doesn’t seem to solve the issue once the car got hot it spuddered and stalled out code for p0251 is still there. unsure if my pump has failed, car starts fine and runs until hot, then dies I’m very frustrated🥲 I have to start taking voltage readings and hope I find something obvious, and hope the the pump or ecu aren’t bad

 

[super1]

So today I slapped a new crank sensor in, it doesn’t seem to solve the issue once the car got hot it spuddered and stalled out code for p0251 is still there. unsure if my pump has failed, car starts fine and runs until hot, then dies I’m very frustrated🥲 I have to start taking voltage readings and hope I find something obvious, and hope the the pump or ecu aren’t bad

Did you use an OEM Sensor?
Could be a wire problem around pump or harness

https://www.engine-codes.com/p0251_volkswagen.html

 

[Dmwitty22]

So after further investigating I noticed the code p0251 in a generic scanner seems the indicate more of a disconnection with the pump, so I unplugged the pump entirely and turned the key over a few time to trigger the fuel temp sensor that should be also associated with the pump being on or off, basically my harness pins on the engine side seemed to be loose and intermittently connected and I guess opening enough when hot to stop the pump from supplying fuel, or the crank sensor was also the cause maybe as it was stiff and had a rub spot near the clips fairly deep. I bent the pins on the engine side harness and filled with dielectric grease and made sure the connector clicked and it’s been fine since haven’t really driven the car on the highway yet but it’s been making to work and back since that