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1st check for spark by removing one of the spark plugs and plug it back into its lead and rest it on the metal of the engine ( DO NOT hold it on place by hand) then have your assistant turn the engine over whilst you watch the plug. It should give a fat blue spark at regular intervals.
If not then check that there's power to the coil pack (at the other end of the plug lead) using a meter. If there’s 12V at the pack but no spark then check the ECU power supply (fuse and relay) and also the connections to the crankshaft speed sensor.
If there is a spark and its still not starting then its likely that the ECU isn't opening the fuel injectors, if the injectors are working you can hear them click - its difficult to hear them with background noise so use a long screwdriver like a stethoscope, placing the handle end in your ear and the metal tip against the body of the injector whilst your assistant turns the engine over.
If you can't hear anything check the ECU power is present by measuring voltage at the fusebox and on its relay socket if OK then check the connections to the crank speed sensor and consider replacing this sensor if the wiring / connections look OK
If the car will start using a squirt of quick/ easi start into the intake then this confirms the problem is lack of fuel
Also its worth checking that the electric pump that feeds the injectors is working correctly, it should run for a few seconds then switch off when you first turn the ignition on. If you remove the filler cap to the fuel tank and listen inside while your assistant flicks the ignition you should hear it clearly
If the connections to this are corroded or damaged then the pump could stop at any time. Check that its relay switches in and out and the relay contacts are clean and bright – replace the relay if in any doubt and do the same for the fuse, ideally measure the voltage at the pump and check its getting 12V.
You should be getting around 3 bar measured at the injector rail check to see if the plugs are getting wet indicating fuel is flowing – if not and the injectors are opening then there’s a problem with the pump or the filter or even the pressure regulator
there is no power at the coil pack. The spark plug wires do not create any spark. I have not checked the fuel system because there is no spark. Before that, I did try starting fluid with no success.
Ok I have power through the fuse labeled "ign run" and the one labeled "ign start". There is no relay or fuse labeled ECU. I have one EAXL relay and one called Auto shutdown. I have swapped several of the relays around as they are all the same but nothing changes.
I guess I need a schematic to see if the ignition switch is before or after the fuse to rule it out or in. Also I need to know what components are between the fuse and coil.
Is there supposed to be power at the coil and the crank sensor tells it when to fire or is there more complexity to it like a computer that decides when to fire the coil for each plug?
If you think I need a computer diagnostic in the shop, I'll do that and still be satisfied with your efforts, especially if you tell me whether it is worth replacing the ignition switch. I see that mentioned in several internet blogs, but not necessarily associated with my problem specifically.
Ok thanks, XXXXX XXXXX info. One last question and then I'll complete the rating. Since you mentioned the "immobiliser" I need to understand what that is and its basic design since I suppose if it was defective, it could cause the ECU to not switch on. Maybe I can temporarily disable the immobilizer to prevent it from shutting down the ECU relay.
Just a follow up, the problem turned out to be the timing belt was broken so the cams were not sending a position signal.