HELP NEEDED

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nesika
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HELP NEEDED

Post by nesika »

Hi guy just joined as Ima at my witts end with this car ive bopught for my son,long story short its a 2005 1.2 one lady owner from new 50K miles full service history,I thought this woud be a cracking first car and is a good base to sport it up a little,anyway bought it off a dealer with a running fault,it keeps dropping onto 2 cylinders (number 1 shuts down) switch it off and it runs perfect then after a fgew revs drops down again,compession is 210/235 so no burnt valves,we have swapped coil pack plus injector and Ive even had an ECU fitted and coded in but still the same faultsmall the wiring has been pinned out and checked all good,all the code reader brings up is nunber 1 miss fire,Iam at a loss where to go next having put all new brakes on the car to get it ready for his 17th birthday I thought I would ask on a forum incase anyone has come accross this problem.
blackertracker
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Re: HELP NEEDED

Post by blackertracker »

Obvious things you haven’t mentioned:
Spark plugs
HT leads

Worn exhaust valve guides are common with this engine I think though, which can show up once engine is revved.
RUM4MO
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Re: HELP NEEDED

Post by RUM4MO »

blackertracker wrote: Thu Feb 07, 2019 7:51 pm Obvious things you haven’t mentioned:
Spark plugs
HT leads

Worn exhaust valve guides are common with this engine I think though, which can show up once engine is revved.
Spark plug leads, there will not be any on this engine I think, as it will have COPs just like your car, spark plug,hopefully that has already been considered, worn guides, yes or maybe the wiring to cylinder 1 has an issue either with the coil firing wiring or the injector wiring.

Edit:- there should be plenty of info on these engines problems on the internet, on this forum, the Skoda forum, ie briskoda.net and the Ibiza forum ie seatcupra.net. Maybe spent some time on all these 3 forums to drag up some good suggestions.
nesika
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Re: HELP NEEDED

Post by nesika »

blackertracker wrote: Thu Feb 07, 2019 7:51 pm Obvious things you haven’t mentioned:
Spark plugs
HT leads

Worn exhaust valve guides are common with this engine I think though, which can show up once engine is revved.
changed plug and leads also changed the engine when I first for it as I was told guides could be the problem,but still the same problem
blackertracker
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Re: HELP NEEDED

Post by blackertracker »

nesika wrote: Thu Feb 07, 2019 8:53 pm
blackertracker wrote: Thu Feb 07, 2019 7:51 pm Obvious things you haven’t mentioned:
Spark plugs
HT leads

Worn exhaust valve guides are common with this engine I think though, which can show up once engine is revved.
changed plug and leads also changed the engine when I first for it as I was told guides could be the problem,but still the same problem
I don’t understand what you mean? You’ve changed the whole engine?

Have you checked the timing, just for the hell of it? These are chain cam engines - might have jumped a tooth. 50k miles/14 years quite low - has it had regular yearly oil changes? I suspect not.
nesika
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Re: HELP NEEDED

Post by nesika »

blackertracker wrote: Thu Feb 07, 2019 9:03 pm
nesika wrote: Thu Feb 07, 2019 8:53 pm
blackertracker wrote: Thu Feb 07, 2019 7:51 pm Obvious things you haven’t mentioned:
Spark plugs
HT leads

Worn exhaust valve guides are common with this engine I think though, which can show up once engine is revved.
changed plug and leads also changed the engine when I first for it as I was told guides could be the problem,but still the same problem
I don’t understand what you mean? You’ve changed the whole engine?
i changed the wholw engine in case it was worn guides or valves as it was cheaper then rebuilding the head i found another low miles engine so bought it and swapped it but still the same fault so I dought both engines would have the same faultly guides or valaves on the same cylinder lol plus this engine has 235/210 compression which is well up so no valve problem there,plus if there was once the engine has dropped onto rwo cylinders as soon as you swithch it off and then restart it the thing runs and revs perfect right up untill you jit around 3000 rpm and then it drops to two cylinders again


Have you checked the timing, just for the hell of it? These are chain cam engines - might have jumped a tooth. 50k miles/14 years quite low - has it had regular yearly oil changes? I suspect not.
RUM4MO
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Re: HELP NEEDED

Post by RUM4MO »

In that case, maybe a wire harness issue on the injector or coil side of things?

I don't know if there is a short section of cable going out to the head area for either or both of them that you could replace - or repair if you find the damage point(s).

Edit:- I know that you have pin to pin'd these areas hopefully, but I think that there is a misfire counter that allows but logs misfires then at a certain number, disables that cylinder's injector to protect the cat, now switching off the engine will reset that counter and so the car will run okay until the misfire counter has again reached a certain number, than could explain what is happening and the harness might be marginal as far as damage is concerned and so when it is warmed up and in place it is intermittently failing.
nesika
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Re: HELP NEEDED

Post by nesika »

RUM4MO wrote: Fri Feb 08, 2019 10:54 am In that case, maybe a wire harness issue on the injector or coil side of things?

I don't know if there is a short section of cable going out to the head area for either or both of them that you could replace - or repair if you find the damage point(s).

Edit:- I know that you have pin to pin'd these areas hopefully, but I think that there is a misfire counter that allows but logs misfires then at a certain number, disables that cylinder's injector to protect the cat, now switching off the engine will reset that counter and so the car will run okay until the misfire counter has again reached a certain number, than could explain what is happening and the harness might be marginal as far as damage is concerned and so when it is warmed up and in place it is intermittently failing.
that did cross my mine my mechanic whom works for me has donr evet check possable but as you say when tested its fine but when running throws a fault,I think I will change the loom as thats still origonal,its down at a local VW garage at the min hes checking it with the VAG diagnostics and it struggling to find a fault otehr then when it shuts down number 1
MAX13
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Re: HELP NEEDED

Post by MAX13 »

I have the exact same problem. The car is going into the garage tomorrow to get new camshaft and crankshaft sensors. I read somewhere that that fixed the problem for someone else.
I will let you know how it goes.
MAX13
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Re: HELP NEEDED

Post by MAX13 »

New Sensors didn't work. Engine failed compression test and showed a valve problem. Going in to morrow for new valves. Will let you know..
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