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Lachlan33
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Lachlan33 Community Regular

Lachlan33

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Ok guys I am officially stumped.

I have had my car off the road for awhile now, trying to DIY fix a problem with it. Its only firing 5 cylinders, the front cylinder (#1? Or is that #6?) doesn't do anything.

I have tried new spark plugs. I have checked to see if there is spark (there is)

I have tried spare fuel injectors.

I have done a compression test and found all 6 cylinders to be consistant.

When starting the car and revving it a little you SOMETIMES get a couple seconds of 6 cylinder goodness then its back to 5.

I just don't know what the go is.

At this point I am thinking about just giving up and taking it to a mechanic, but I would like to be able to fix it myself as it's the only way I will learn :D

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paulr33 Grand Master

paulr33

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what did you last change? when did it last work?

what ecu? have you tried stock ecu diag or consult check of all basic sensors?

have you checked all wiring, plugs, loom, fuses

have you tried swapping plugs to see if the "no fire cylinder" follows ?

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Lachlan33 Community Regular

Lachlan33

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It wasn't a problem that just appeared one day. It came gradually over several months. It would be fine 95% of the time then sometimes be on 5 cylinders for no reason. Then over the months that got worse and worse until its 5 100% of the time.

I have tried swapping plugs yes, its not a spark problem.

One idea I had was that it might be the plug going to the injector. I tried connecting the plug to a spare injector while the engine was running to see if the spare injector did anything. It did not. Now thats either because there is indeed no signal getting through, or (what I suspect) it would be impossible to tell if it was doing anything just by holding it while its plugged in.

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Guilt-Toy Grand Master

Guilt-Toy

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Posted
It wasn't a problem that just appeared one day. It came gradually over several months. It would be fine 95% of the time then sometimes be on 5 cylinders for no reason. Then over the months that got worse and worse until its 5 100% of the time.

I have tried swapping plugs yes, its not a spark problem.

One idea I had was that it might be the plug going to the injector. I tried connecting the plug to a spare injector while the engine was running to see if the spare injector did anything. It did not. Now thats either because there is indeed no signal getting through, or (what I suspect) it would be impossible to tell if it was doing anything just by holding it while its plugged in.

can you check something for me?

go look at your ECU, open the kick panel. check to make sure the ECU is plugged in ALL the way. I have seen many cars have issues like this when the ECU is not pluged in correctly.

Check to make sure the plug is in ALL the way into the ecu, if you are unsure then unplug the ECU and take notice of when plugging it back, sometimes you need to screw the 10mm bolt in a few turns then press in both sides of the ecu plug so the end of the plugs go in with it - repeat this untill the 10mm bolt wont go in anymore (dont force it- within reason)

do you have a series 1 or series 2 engine ? it could also be the ignitor

Do this and report back with results

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Lachlan33 Community Regular

Lachlan33

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YAY I fixed it.

I connected a spare injector to an external power source and noticed they make a clicking noise. When that same injector was running off the loom plug, I noticed no such noise. I cut the plug off, did a quick bodgy wiring job, started the car and bam, 6 cylinder goodness!

So it was the loom plug. Thanks everyone for your help and suggestions. I will now go and tidy the wiring up so its not dodgy (where did I put my gaffa tape....)

I am so glad I have FINALLY worked out this damn problem.

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