Fuel shut off solenoid

My discovery has developed a mistery fault.It sometimes would crank over but not start.Found out fuel solenoid not working.I changed this for a new one.It started fine but now has started doing it again.It seems sometimes the voltage at the lead going to the solenoid goes, making it stop.It happens sometimes while driving.Where does that wire go to looks like in the workshop it goes to the ecu.Any ideas Thanks

You need to fit part # AMR4956.

What part is that?

brandysnaps said:

My discovery has developed a mistery fault.It sometimes would crank over but not start.Found out fuel solenoid not working.I changed this for a new one.It started fine but now has started doing it again.It seems sometimes the voltage at the lead going to the solenoid goes, making it stop.It happens sometimes while driving.Where does that wire go to looks like in the workshop it goes to the ecu.Any ideas Thanks

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I have seen this happen when the earth braid to the starter was loose, it seemed there was just enough earth to allow the starter to crank albeit it slower but left insuffcient 'earth' to allow the solenoid to operate which seems odd because the earth requirement is not that high on the solenoid.

Bu true to form the car always started on a push and sometimes on the key, I run a jump lead from battery earth to metal on the engine and away she went, the intermittent cutting out disappeared as well!

Replaced earth braid (starter to body) and all was well, might be worth a look?

regards

Dave

My mate has this problem with his 300Tdi, we have put an extra earth lead from where the air con pump would sit but she is still doing it.
we checked the voltage to the fuel shut off solenoid and sometimes it's at 12V and others it's at 2V.
We ran a switch feed direct from the battery to the blanking plate in the cab and back to the solenoid.
When the switch is live she doesn't quit but if you turn the ignition off she still runs so might make it easy to steal.

There has to be something that is cutting the volts to this and it might be a dry joint on the Spider, but thats a big job to get it out.
Let you know how we get on.

Stu