Mk4 golf gti agu electrical issue

[Jamiebain1981]

Got back from work today went to go out car struggled to start rev counter jumps all over the place fuel relay is clicking really fast fuel pump is going on and off injectors are going on and off throttle body clicking coils sparking once I get car started takes a while it runs fine anyone know what could be the problem

[mike1990]

Vacuum leak?

[Jamiebain1981]

It's doing all that before cars even started as soon as I turn ignition on to second click

[sharki786]

Dodgy ecu or fuel pump relay or crank sensor

[Jamiebain1981]

I've tried fuel relay and unplugged crank sensor is there anyway off testing ecu if I get it plugged in will it show a fault code if it's ecu

[northeast_gti-t]

I've tried fuel relay and unplugged crank sensor is there anyway off testing ecu if I get it plugged in will it show a fault code if it's ecu

afaik if you connect up to vag com and there is an ecu fault it should flag it up

[Jamiebain1981]

Ok will find someone to hook it up for me and see what happens

[Jamiebain1981]

No communication when trying to connect to ecu and car takes ages to start now and cuts out

[james2]

I would check the battery out first and its connected tight. My old xr2i did this once, turn out to be the battery was very weak so i replaced it.

[sharki786]

If its not connecting then i would check the ecu fuse. My mate had same problem and the diagnostics wouldnt connect turned out that a fuse poped