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OK as you've already replaced the cam and crank sensors the next thing is to check if the ECU has electrical power with the ignition on
if you use a voltmeter in the engine bay fusebox to check if there's 12V on the ECU fuse
if you have ECU power but still no spark then follow the wiring loom back from the crank sensor and check it for damage and corroded connections between the sensor and the ECU
and if this is OK then the best test is to disconnect the ECU and also measure the continuity between the ECU socket and the sensor connection
if the continuity is there, then we're into a replacement ECU
so the ECU has power and the wiring between the ECU and sensor checks out OK?
so if this is true then ideally the next step would be to plug in a scan tool thats capable of monitoring and check to see if the crank speed signal is coming in during cranking
if it is and the ECU still isn't sparking I'd next check to see if the injectors are clicking so checking to see if the ECU is trying to fire that side
if the injectors are not triggering then I'd say either the ECU has a fault or the security system is preventing the start
however if this was the case normally the engine wouldn't crank / turn over either
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have you had a chance to see if a crank signal is making it back to the ECU as I've suggested ?
Ok so if there's crank speed coming into the ECU
and you can communicate with the ECU to view this then the ECU must also be powering up as well
so the next step is to check if its injecting
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 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 clearlyIf 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
Could also be incorrect fuelling due to a faulty water temp sensor. If this is the problem then the ECU will never add the 'cold start' extra fuel required if the car starts OK when warm then I 'd look into changing the sensor.
Ok to summarize then
there's no sparks
there is ECU power
there is a crank speed signal
there's no injector signal?
does the fuel pump run?
If these too are not present then I'd say that either there's a wiring fault or the ECU is faulty