Injectors not working on a non start prob

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ceetee25
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Injectors not working on a non start prob

Post by ceetee25 »

Can anyone tell me if the injectors on DJ should have volts on them when you turn the ignition on without cranking the engine. Mine dont and needless to say they dont work in any of the tests. The fuel pump operates for the 3 secs when ign turned on. Cranking the engine presumably pulses earth conns from the ECU to operate them so its more than likely an ECU prob anyway.
Van ran fine - then ,switched off go to restart - nada. This alone leads me to believe its electrical as no symptoms of any bad running beforehand.

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bigherb
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Re: Injectors not working on a non start prob

Post by bigherb »

The injectors are powered by the fuel pump relay so are only powered when the fuel pump its running and as you say they are earth switched by the ECU.
1982 Camper 1970 1500 Beetle Various Skoda's, Ariel Arrow

ceetee25
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Re: Injectors not working on a non start prob

Post by ceetee25 »

many thanks.
i have rechecked fuel pump relay and not getting the eth trigger from ECU to operate relay. Coil and ign module seem ok wiring wise and there is spark on the ign side so assume that is pulsing the ECU as well.

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bigherb
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Re: Injectors not working on a non start prob

Post by bigherb »

Never assume always check. As the ECU earth switches everything check the ECU earth as well.
1982 Camper 1970 1500 Beetle Various Skoda's, Ariel Arrow

ceetee25
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Re: Injectors not working on a non start prob

Post by ceetee25 »

true assumption is the mother of all £$%^'s ,but when it comes to the ECU you can only go so far unless you buy the Shoebox tester.
In my case i bought another ECU (EXPENSIVE) but fairly sure i had done all the testing without measuring outputs or inputs for that matter to and from ECU. I will get my original repaired at ECU doctor so I will have a spare!!
Anyway its running again.

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