XC70 injector#5 circuit stuck open...

[MtnMann]

Injector #5 is stuck wide open. Injector is fine. When harness is attached to #4 it makes #4 stick wide open so I know it's not the injector.

Any ideas of what to look at next?

[MtnMann]

Can anyone tell me if there is anything else between the ECU and the injector that controls the injector?

I don't have a manual but if there's nothing else in the circuit then I could assume either wiring or the ECU itself is at fault.

[Willy]

Perhaps the pdf can be of help.
I would take a closer look at het wiring.
Willy

[jda2000]

remove the wire loom and check the wiring closely for injector #5.

sometimes one of the wires is broken or crushed by accident when the spark plug cover is removed and retightened.

[Aviator]

That's an odd issue to be dealing with. Normally, the ECM would be at fault as injector operation is controlled from it. Are you getting a flooded cylinder, misfire, fuel pressure bleeding off?

Dave.

[MtnMann]

Thanks for the replies...

Yes. Flooded cylinder and misfires. With the fuel rail pulled, #5 opens up when the engine is cranked and (i believe) stays open until the key is turned off. So full current is apparently being sent to the injector. Wouldn't a cracked wire in the loom just cut current to the injector?


#5 plug is washed clean with fuel. Other 4 plugs are black indicating rich condition.

Codes showed up for all cylinders both open circuit and misfires. But after pulling the injectors, #5 is clearly the one acting up.

[MtnMann]

someone on another board suggested fuel injector relay.

Wouldn't that affect the other injectors as well if it stuck?