Next time it refuses to start don't wait for it to make up its mind-do below immediately to determine if its fuel or spark problem
Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, Do you hear the fuel pump come On when you turn key on? If not check fuel pump fuse and fuel pump relay if okay-check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs, coil's resistances, cap and rotor, distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing.
April, 14, 2011 AT 12:57 PM
Thank you for the answer. All above was done, I have replaced the CAM Belt, The "actiator"? The 2 relays above the gearbox, the fuel pump and fuel filter, and a new computer is on order. My car is standing at a dealers workshop for 7 weeks, they cannot find the fault.