hello everyone need some help!!

i have a 2001 land rover defender TD5 it has issues starting i have it at my local garage and they dont know what it is they have replaced a load of parts and have got it down to...

you turn the key and it does not turn over the engine and does nothing but when you spray quick start spray into the air intakes and then turn the key it fires straight up.

what is the issues please help!

when you turn the key the car turns over but does not start

they have replaced the pump

it only starts when you spray quick spray in the air intakes

 

l had exactly the same issue with a 2005 TD5 and it was the starter motor.

lt turned the engine over fine but was generating electrical interference which corrupted the ECU.