Just thought I'd post about a job I did recently that may help someone else with a similar problem in future. Hyundai 80CR-9 with cranks but no start fault. Fault codes - note that not all of these were present all of the time, they were intermittently changing and coming and going. 1210-3 Engine fuel rack position sensor: shorted to high source 1210-4 Engine fuel rack position sensor: shorted to low source 638-3 Engine fuel rack actuator shorted to high source 638-7 Engine fuel rack actuator mechanical malfunction Basically found 3 wires had rubbed through in loom by rear engine mount, there was a bit of moisture around when the fault was happening, so was intermittently shorting high and low to the position sensor signal wire. You couldn't see this on a multimeter and I didn't hook up my scope but if you had of scoped the rack actuator position sensor while cranking I'm sure you could have seen a 0-12v spike where it should be varying between 0 and 5v. The ECU obviously was looking for the rack position to match a preset value and when it didn't decided it must have been a mechanical fault.
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