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evenin, a couple of days ago my car started up on 5 cyl. but after a few miles it was up to full 6 again and was all good :-) but today as i was driving i lost a cylender again :-( but again it came back fairly quickly. whats the diagnostic procedure here then? cheers

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Usually culprits for this tends to be dodgy wiring either on the coil packs or injectors. Give them a nudge when it's idling to see if one drops out. Not very scientific but I found a dodgy one doing it this way.

evenin, a couple of days ago my car started up on 5 cyl. but after a few miles it was up to full 6 again and was all good :-) but today as i was driving i lost a cylender again :-( but again it came back fairly quickly. whats the diagnostic procedure here then? cheers

 

Obviousley playing hide and seek......:confused1:, I used to keep one eye open, and watch where they hid, so keep one eye on your cylinders, you may catch where it goes.......:whistling::whistling:.....Sorry buddy, serious answers only please.....lol:taz:

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Obviousley playing hide and seek......:confused1:, I used to keep one eye open, and watch where they hid, so keep one eye on your cylinders, you may catch where it goes.......:whistling::whistling:.....Sorry buddy, serious answers only please.....lol:taz:

 

sneeky bugger int it! lol

I have the same problem but usually accompanied by a tapping lifter.

 

Mine does the exact same thing, I go push all my coil pack plugs back on and it works fine. Hasn't done it for ages now either, used to do it a lot when the car was a daily driver.

problem i had was cylinder 6 not firing at all, ok i subsequently found out it was firing, but there was a whole in the piston, but don't count on that being your problem.

 

Reason i say it, was i had the same advice - check the wiring, only problem with that, is its a brand spanking new wiring loom on my blue one, but check the spark plug, it might be in its final stages of life.

best to narrow down which cylinder has the miss fire. Mine was doing the same so i unplugged each coil pack in turn to locat the miss fire which turned out to be on number 6. I then cheacked the coil pack plug connecter which was s**t so i replaced but still had a miss fire. Turned out to be bad connection on my injector which once cleaned up fixed the miss fire and has been fine ever since.

Had this problem at the weekend and spent a couple of days chasing it round.

 

Go to each cylinder as it's running and pull each coil pack connector off one at a time and listen.

 

The engine revs drop and you should find removing and refitting one of them will remove the dodgy cylinder. Once you find the engine note drops and there's no missing you'll know you've found the right cylinder.

 

Swap coil packs (obviously with the engine off!) with the neighbouring cylinder and repeat the test with those 2 cylinders.

 

If the cough remains on that cylinder it's either the connector needs cleaning or the injector plug is knackered/dirty.

 

Happy hunting! :)

  • 2 weeks later...
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hey guys! ive tracked down the missing cylinder (its dead all the time now) to the one at rear left if your facing the engine (closest to the brake servo)

anyways ive swapped coil packs and its still that one thats dead, whats the next most common fail? and what else can i do to diagnose the fault? cheers

hey guys! ive tracked down the missing cylinder (its dead all the time now) to the one at rear left if your facing the engine (closest to the brake servo)

anyways ive swapped coil packs and its still that one thats dead, whats the next most common fail? and what else can i do to diagnose the fault? cheers

 

Check the spark plug matey, swap it for a good one (not out of the other cylinders just in case your getting oil on it)

 

Also check for a spark on the plug, take the coil pack out, and plug, put the plug back in the coil pack, place the spark plug threads on the plenum so it earths, and then get someone else to crank the engine and check for a spark across the gap.

Check your main ecu connector , either too tight or too lose can cause this , mine started on 5 a few weeks ago and we tried everything to trace the problem , then i remembered reading about this cause , although i,d had the ecu out it ran perfect after originally re-fitting it , so i loosened it , made sure it was seated right and tightened it up again and hey presto no misfire :thumbup1::thumbup1:

Worth a check even though you might not have touched it .

hey guys! ive tracked down the missing cylinder (its dead all the time now) to the one at rear left if your facing the engine (closest to the brake servo)

anyways ive swapped coil packs and its still that one thats dead, whats the next most common fail? and what else can i do to diagnose the fault? cheers

 

i had this problem when i first bought my z, i was running on 5 then 4, checked coil packs and plugs and it wasnt the problem, so then moved onto injector plugs and found my problem straight away.. i belive that the injector plugs are constant live? so with this they scale up like a kettle and the connections are then dud.... so a bit of warm vinigar and a bit of wet and dry on all the connections and she runs sweet as a nut now !:clap:

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after further investigation, ive got 2 cylinders down :-( rear left and front right. im getting a spark, but the injector plugs are furry as hell. whats the best way to de scale the female half (loom half) of the connection? cheers

 

and im a little puzzled as to why the other one has stopped firing now??????

after further investigation, ive got 2 cylinders down :-( rear left and front right. im getting a spark, but the injector plugs are furry as hell. whats the best way to de scale the female half (loom half) of the connection? cheers

 

and im a little puzzled as to why the other one has stopped firing now??????

 

howdo mate the best way i found to clean up the connectors is to use warm vinegar warm it in the microwave, get some very fine wet and dry or something a little coarse, fill them up with vinegar n wait for the scale to lift, it is a bit of a patience game, but when all connections are clean wd40 all the connector plugs before clicking them back together, and it will fire up no problem

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cheers pal., but it gets stranger :-( i tried with a little wd40 and a tiny screwdriver, on the front right cyl. and both seem to have come back???????? but now its tapping like crazy! wtf is going on??????

cheers pal., but it gets stranger :-( i tried with a little wd40 and a tiny screwdriver, on the front right cyl. and both seem to have come back???????? but now its tapping like crazy! wtf is going on??????

 

yea well while your there you might as well do all 6 male n female connections while your there for piece of mind, as regards for the tapping i didnt experience any when all my cylinders came back online, just quite a bit of soot out of the right exhaust for a minute or two lol ! im guessing the tapping is a sepearate issue to ure firing problem, but thats as far as my knowledge stretches sorry pal

  • Author

ill give all 6 a good clean tomorrow, and the tapping has been an ongoing issue, was just worse than usual tonight. thanks for your help :-), and bill, bbq at mine in wrexham on sat, your very welcome :-)

ill give all 6 a good clean tomorrow, and the tapping has been an ongoing issue, was just worse than usual tonight. thanks for your help :-), and bill, bbq at mine in wrexham on sat, your very welcome :-)

 

hey no worries dude :thumbup1: hey i would love to take ure invite but i got my little lad this weekend... ( have him every other weekend) ... so ill be gettin him to hoover the zx :tt2: another time though defo! cheers bill

has your zed been off the road while you have been trying to sort your miss fire? if so you could just find you have a sticky tappet and needs a good run to make it quiet again.

I had a very similar problem two weeks ago now, was the day I was supposed to be driving to London to work from the office for 3 days. I'd done my oil change, put my new auxiliary belts on etc. pulled it out the garage and it started miss-firing, tried all the coil pack connectors as they are known to be bad on my car, I have replacements but now also need coil packs, so holding off on fitting them. Anyway, turned out one of my injectors had gone down, the very front left as you look at the engine. Pulled the connector off and sure enough, furry as hell. Went and got some good old fashioned connection cleaner from halfrauds, sprayed it up and it's been fine ever since. I've wanted to do the rest of mine too, but they're a little stiff to come off and tbh I don't wanna break what currently works, lol.

This is a really silly question but how do i know if i have a miss fire? occasionally my revs hunt loads, and then it stutters a bit when it's given some throttle, only happens occasionally but it seams to be getting more regular. at first i thought it was the throttles being misaligned but I've checked that and they're both fine so I'm sort of stuck now

This is a really silly question but how do i know if i have a miss fire? occasionally my revs hunt loads, and then it stutters a bit when it's given some throttle, only happens occasionally but it seams to be getting more regular. at first i thought it was the throttles being misaligned but I've checked that and they're both fine so I'm sort of stuck now

 

hi mate you will find your rev range is really unsmooth for example when i let my car idle when it was missing it it seemed okish, but if i put my foot to the floor sharply the whole car was shaking and it sounded well.. not nice, u should notice it more between 1k n 3k

  • Author
has your zed been off the road while you have been trying to sort your miss fire? if so you could just find you have a sticky tappet and needs a good run to make it quiet again.

 

only been standing for a few days, but as i said, i do suffer from sticky lifters, so not too bothered really about the tapping at the moment.

 

 

 

ive been askig some of the mechanics in work about the green fur, and they all said hot water, what do you think? also they sugested that the injectorsd may share the same earth and thats why cleaning one plug seemed to help the other cyl?

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