if the engine starts and runs then its not the immobilser
also check the connections to the EGR valve, if either the vacuum pipe of electrical connection are damaged / corroded then the EGR can be on all time which certainly will hurt performance. Its also possible that its a fault with the EGR valve so its worth removing the valve and cleaning it out with brake cleaner, if it looks particularly clogged then replace it.
If this is OK then check the small vacuum lines to the turbo and its connected control solenoid on the bulkhead, any cracks or leaks can give turbo issues and its best to have the boost pressure measured actually measured with a boost gauge to check that the turbo is healthy and that the sensor is reading correctly
hello, yes but it does run so I don't think its the immobiliser, if it was then it wouldn't crank or start
my 1st thought is a lack of fuel to be honest but if you're confident the fuel supply is OK then it could also be an injector leaking fuel back through the overspill pipe, so not getting enough fuel pressure to tell ECU to fire the injectors, this is trickier to find and you’ll need the garage to do a ‘run back’ test to identify which one is the issue
yes new keys need to match the ECU otherwise the security won't work properly
do you still have the old key?
does it start up on that?
next thing to check is if the ECU power is being lost when the engine dies?
as this will prove if its as security system issue or not
so if you use a meter on the ECU fuse and try and start the engine , check if the voltage drops out
OK so the ECU isn't losing power then its definitely not the immobiliser
I'd go back to the engine and this time check over the electrical side
This could be a wiring issue as things tend to expand when hot and its possible a poor or partial electrical connection is being pushed apart on one of the major sensors so check the connection plug and wiring to the following;
Crank position sensor
Cam position sensor
Throttle position sensor
unplug each in turn and use some switch / contact cleaner spray on the pins to ensure its all grease / dirt free
Also worth checking the connections to the fuel pump for the same reason - unplug each in turn and give them a good squirt of switch / contact cleaner - Not WD40
and also unplug and inspect the main power relays and fuses for signs of overheating or corroded terminals - so the ones for the ECU and the fuel pump
And also unplug the wiring loom connections in the engine bay one at time and inspect for corroded or recessed pins.
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