4BT shuts off at speed (1 Viewer)

[Torq]

I'm running a 4bt in a 96 Land Cruiserand yesterday it started to cut off when I was hitting 50mph+. First it loses power and becomes unresponsive to throttle increases/decreases, then the engine dies. I can drop the transmission (4L80E) to neutral and restart the engine and usually resume driving as long as I don't push the throttle.

I assumed it was a clogged fuel filterso I replaced the inline (between tank and pump) and the main (between pump and injector). I took it for a shakedown and pushed 75mph with no dieing (yesterday evening).

However, after running it at ~60mph for around 5-6 miles this morning, the engine cut out again. I added some PS Kleen and fresh diesel to the tank, but I doubt that'll really address the issue. Any idea what would cause this? It's an electric fuel pump; is that a binary failure mechanism, or might the pump performance slowly degrade? Thanks for any comments that might help.

 

[lckarl]

If you are confident that your fuel is now clean and is not impeded from getting to your injection pump, I would make sure that all of your wiring to your electric pump is in order. What type of injection pump do you have?

 

[Torq]

If I was getting fuel up to 55mph, I suspect the wiring to the electric inline pump has to be ok. However, the wiring elsewhere on this thing has been dismal and I've been working through some of the poor/nonsensical splices and wiring decisions made throughout the previous owner's build. Haven't ruled out that the sock is still installed on the pick up line inside the tank and I read on 4btswaps that it shouldn't be...

Injection is a P pump I believe:

 

[Wheelingnoob]

So it's a non electric pump then only thing electrical is the fuel cut to stop the engine when the key is turned off.