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I don't know if this will save you from taking the panel off, but the fuel pump resistor bypass relay is also energised for ~2 seconds when you start the car to pressurise the fuel system. Turn the ignition on without starting it and you will hear the click on and then off in the bulkhead (at least I do on mine) and you may be able to identify if this is the click you're hearing. I also hear the click occasionally while accelerating, [USER=26435]@Old Guy[/USER]'s hearing notwithstanding. I think if the injector fuel flow exceeds the pump with it's reduced baseline voltage due to the series resistor, the ECU triggers more fuel pump voltage and pump flow by bypassing the series resistor. Of course the fuel pressure is low when you initially start the car, but I don't know if the relay is triggered by the low pressure or a preprogrammed 2 energized interval during starting.

<blockquote data-quote="Wild Turkey" data-source="post: 2091899" data-attributes="member: 37580"><p>I don&#039;t know if this will save you from taking the panel off, but the fuel pump resistor bypass relay is also energised for ~2 seconds when you start the car to pressurise the fuel system. Turn the ignition on without starting it and you will hear the click on and then off in the bulkhead (at least I do on mine) and you may be able to identify if this is the click you&#039;re hearing. I also hear the click occasionally while accelerating, [USER=26435]@Old Guy[/USER]&#039;s hearing notwithstanding. I think if the injector fuel flow exceeds the pump with it&#039;s reduced baseline voltage due to the series resistor, the ECU triggers more fuel pump voltage and pump flow by bypassing the series resistor. Of course the fuel pressure is low when you initially start the car, but I don&#039;t know if the relay is triggered by the low pressure or a preprogrammed 2 energized interval during starting.</p></blockquote><p></p>

[QUOTE="Wild Turkey, post: 2091899, member: 37580"] I don't know if this will save you from taking the panel off, but the fuel pump resistor bypass relay is also energised for ~2 seconds when you start the car to pressurise the fuel system. Turn the ignition on without starting it and you will hear the click on and then off in the bulkhead (at least I do on mine) and you may be able to identify if this is the click you're hearing. I also hear the click occasionally while accelerating, [USER=26435]@Old Guy[/USER]'s hearing notwithstanding. I think if the injector fuel flow exceeds the pump with it's reduced baseline voltage due to the series resistor, the ECU triggers more fuel pump voltage and pump flow by bypassing the series resistor. Of course the fuel pressure is low when you initially start the car, but I don't know if the relay is triggered by the low pressure or a preprogrammed 2 energized interval during starting. [/QUOTE]

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