Heres one for the electrical specialists among you wise folk.
Mate's 110 TDI died the other day. Quick check showed fuel shut-off solenoid was not getting power when the ignition was on. Traced the fault back to the engine compartment multi-pin plug on the bulkhead, where the pin had broken off in the socket. The break looked as if it had been a little burned, but I put that down to arcing during its weakening state. Easy repair, just ran a bypass wire around the multi-pin plug, power was restored to the solenoid, and off she went. Few days later, the problem has reversed.....now the engine wont stop!!
Even with the ign. off, there is still power to the solenoid. The solenoid itself seems to be ok, clicking nicely when power is disconnected and reconnected, but the only way to kill the engine is detatch the spade connector from the solenoid. Question 1 - Is there a relay in that circuit that could have failed in the 'make' position? Question 2 - bearing mind the burned appearance of the previously broken pin, could the solenoid be pulling way too much current thus causing pin meltdown/ relay terminal welding? Seems odd that its had 2 failures in the same department in a matter of days. Any bright ideas would be welcomed!
Mate's 110 TDI died the other day. Quick check showed fuel shut-off solenoid was not getting power when the ignition was on. Traced the fault back to the engine compartment multi-pin plug on the bulkhead, where the pin had broken off in the socket. The break looked as if it had been a little burned, but I put that down to arcing during its weakening state. Easy repair, just ran a bypass wire around the multi-pin plug, power was restored to the solenoid, and off she went. Few days later, the problem has reversed.....now the engine wont stop!!
Even with the ign. off, there is still power to the solenoid. The solenoid itself seems to be ok, clicking nicely when power is disconnected and reconnected, but the only way to kill the engine is detatch the spade connector from the solenoid. Question 1 - Is there a relay in that circuit that could have failed in the 'make' position? Question 2 - bearing mind the burned appearance of the previously broken pin, could the solenoid be pulling way too much current thus causing pin meltdown/ relay terminal welding? Seems odd that its had 2 failures in the same department in a matter of days. Any bright ideas would be welcomed! 
