What actually happens when you try starting the car?
Dead? Check cut off switch on bulkhead on lhs.
A Click and nothing else? Check battery and condition of connections, starter motor etc. Tap the motor/solenoid carefully to see if sticking/ brushes not in good nick.
Engine turns but does not fire?
Check fuel/pump. Check spark. Plugs,leads,etc
Check pipes etc for splits....air being sucked in etc.
Use fault code reader as that might home in on faults to save methodical long testing or checking due to the complexity of Gems and reliance on several sensors/components.
Gomog has a link to Gems manuals and shows the locations of components and "theory".
Back to basics "try the simple things first" often finds the problem without hit or miss trial and error of
Good luck!
