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Discussion Starter #1
Hi guys,
I'd like to pick your brains please. I'm losing cylinder 8 regularly. Popped my peake reader on and it gave me error 23. Fuel injector 8. Limped it to the workshop and put INPA on and after a reset to remove all codes (ebox fan and cts implausibility) it returned the same error, although INPA calls it injector solenoid.

Figuring that having done 180k miles now she deserved a new set of injectors anyway (all sensors are new on her as I change them before they die on all my vehicles) I threw a new set in. First mistake. No change.

Took plenum off and inspected all wiring, all seems to be in order. Also unplugged ecu, cleaned connector with connector cleaner, let it dry and reconnected them all but with injectors 7 and 8 swapped and also coils 7 and 8 just in case either:

A) I got one duff injector and amazingly fitted it to cylinder 8
B) the issue was really coil related and not injector.

Same problem, she loses cylinder 8' pops the MIL on and flags code 23.

Any of you guys already been here and done this to save me a lot of headache and maybe cash?
 

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Can you bring up the "cylinder unrest" graph while running at idle and see if it looks off/weird?

When you changed the injectors, did you look into the fuel rail at all?

Next thing could be to make sure you have power at that injector by unplugging it and hooking up a noid light. Fire up the engine and make sure it lights up.
 

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Discussion Starter #3
Hi, sorry, I really should have elaborated, this error appears after about 10 mins driving. It's not a permanent fault so the error is intermittent and related to either vibration or heat. I'm not flagging any misfire errors at all so have ruled out fuel delivery to injectors and the cylinder unrest table looks normal. The annoying thing is I can't replicate the fault at rest and of course the whole inlet and trumpets etc have to come off to get to the injectors or wiring so by the time it's in a testing state it's a non runner.

Had hoped someone on here would have previously been here and worked through this headache to a solution and that it was quite "common" but if not - I will keep at it and let you guys know the end solution.
 

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Hi, sorry, I really should have elaborated, this error appears after about 10 mins driving. It's not a permanent fault so the error is intermittent and related to either vibration or heat. I'm not flagging any misfire errors at all so have ruled out fuel delivery to injectors and the cylinder unrest table looks normal. The annoying thing is I can't replicate the fault at rest and of course the whole inlet and trumpets etc have to come off to get to the injectors or wiring so by the time it's in a testing state it's a non runner.

Had hoped someone on here would have previously been here and worked through this headache to a solution and that it was quite "common" but if not - I will keep at it and let you guys know the end solution.
Rats. I didn't know it wasn't a hard fault. hmmm. Hopefully someone will chime in that has had a similar issue. Only other thing that comes to mind is DME itself has a problem? If you have access to a wiring diagram I would start perusing the injector harness. Maybe you have a ground or even power wire that is about to break, so the current draw makes it get hot and lose connection? I've see stranger things happen!

Good luck,
 

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Discussion Starter #7
Rats. I didn't know it wasn't a hard fault. hmmm. Hopefully someone will chime in that has had a similar issue. Only other thing that comes to mind is DME itself has a problem? If you have access to a wiring diagram I would start perusing the injector harness. Maybe you have a ground or even power wire that is about to break, so the current draw makes it get hot and lose connection? I've see stranger things happen!

Good luck,
That is exactly my worry. Will do some more testing today.
thanks for your time guys, really appreciate it.
 

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any luck on chasing this problem down? Mine never hits limp mode, but definitely stumbles on sharp throttle stabs. Another member pm'd me about this as well -- seems to be a wiring issue since we're all getting this peake code 23 (cyl 8 injector) :Thumbdown:

anyone?
 

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23 is for an electrical problem as you say. The DME is seeing a short or a ground in the circuit. Is this a random problem like the OP's or steady?

Do you have DIS? It has a test which fires injectors on and off with the engine off so you can listen for the clicking.
 
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