Hi

I have a 2001 X1 that I keep at my holiday house and use once a year for a month while i'm there.
It has run fine over the last few years - some hesitation at certain throttle settings in the past but not enough to worry me.
This trip when I got here it would not start.
I drained and replaced the fuel, fuel filter and spark plugs and now it runs fine in neutral.
It will rev freely from idle to the redline in neutral.
If I try to accelerate in 1st gear (under load) it dies after 5-10 metres.
After it dies it will not start immediately unless i prime the fuel system (turn key on and off 2-3 times) and then it will fire up no problem. This makes me think it is a fuelling problem.
I have done a tps reset. Idle is about 1000, TPS @ 4.4 degrees.
I have removed the fuel hose from the pump side of the fuel filter and tested the pump pressure by hand and it feels super strong (not sure if it is valid to detect low pump pressure this way or if a subtle lack of pressure will impact fuelling so drastically - I thought that for it to die so quickly there would have to be a substantial lack of pump pressure).
I ran ECMspy to check for error codes and was showing code 23 (front injector voltage) but that has gone now (I ran injector cleaner so not sure if that could have helped or if this is an electrical connection only)

I'm not sure where to go form here. Have searched the forums to get this far but not found a similar issue yet.


Any ideas?

Cheers

Matt