Author Topic: missing on 1 cylinder  (Read 1146 times)

Offline av8r

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missing on 1 cylinder
« on: 05 March 2011, 12:06 »
Hi again everyone, my 98 Gti 8v (dont know the engine code- how do i find that out?) started missing on a cylinder (#4 i think, the far right one looking from the front of the engine anyway). Checked continuity through the HT lead, no prob, took the plugs out and in the 3 working cylinders they were black, i.e running rich but #4 was "dry". Checked the spark on the plug and that was good so that points to a fuel supply issue. Coaxed the car down to my local trusted garage. The injector seals were perished and they thought air was getting drawn through causing cylinder to miss. They changed them but the problem is still the same. The electrical pulse was also a bit weak, but its atomizing fine with the injector out. Compression test is good so its not anything with the valves. Any ideas? Having done a big search on here i'm suspecting the injector wiring loom, but is there anything else it could be? Also if it is the wire in the loom is it possible to rewire it or will it be megabucks for a new loom? I know scrappers might have one but then with another old loom the same thing might happen next week. Has anyone else had similar symptoms and if so what was the fault/fix?  The car has been out of action for 10 days now and i'd be grateful for any pointers thnx.

Offline forsh

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Re: missing on 1 cylinder
« Reply #1 on: 05 March 2011, 17:49 »
 i know you say the spark plugs working,but try changing the plugs round to see if its giving a big enough spark,also change th leads around to see that also


Offline Wayne

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Re: missing on 1 cylinder
« Reply #2 on: 05 March 2011, 19:46 »
Coilpack, duff lead or plug.

Offline av8r

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Re: missing on 1 cylinder
« Reply #3 on: 06 March 2011, 16:18 »
Thnx for the replies. Garage changed plugs already and used sparktesters on all of them and all firing fine. With regards to the coil pack possibly breaking down how could it affect just one cylinder?? If it somehow is the coil, it would be the third one in as many years!  :shocked:

Offline neil1780

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Re: missing on 1 cylinder
« Reply #4 on: 06 March 2011, 16:46 »
Could be a duff injector mate I would try this next before the loom
V6 4MOTION

Offline cobalt6700

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Re: missing on 1 cylinder
« Reply #5 on: 06 March 2011, 20:29 »
What's the dizzy like? Are the spark gaps ok?

Maybe a blocked injector? If you swap injectors does the misfire move?

1993 GTI 8v 5dr matt black and green - the 'sh!tball rally car'
1997 GTI 8v 3dr metalic black - the daily driver
2002 3DR 1.8T AUM silver - the new daily
1993 Jeep cherokee 4L - the weapon :D

Offline Wayne

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Re: missing on 1 cylinder
« Reply #6 on: 06 March 2011, 20:52 »
You might have a ecu problem  :smiley:

Offline av8r

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Re: missing on 1 cylinder
« Reply #7 on: 07 March 2011, 21:20 »
I dont know what to make of it anymore and neither does the garage! plugs firing ok, injectors atomizing ok but running very very rich and intermittently now missing on 1 or 2 (!) cylinders. Fault code indicated oxygen sensor as well. Garage changing this as well but not heard back from them by close of play today. I can feel the £'s accumulating lol.....and on that subject, if it is the ECU i guess that will be more than the car is worth?

Offline Wayne

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Re: missing on 1 cylinder
« Reply #8 on: 08 March 2011, 00:02 »
I dont know what to make of it anymore and neither does the garage! plugs firing ok, injectors atomizing ok but running very very rich and intermittently now missing on 1 or 2 (!) cylinders. Fault code indicated oxygen sensor as well. Garage changing this as well but not heard back from them by close of play today. I can feel the £'s accumulating lol.....and on that subject,
if it is the ECU i guess that will be more than the car is worth?

S/h ones available if needed on ebay etc.

Offline thai-wronghorse

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Re: missing on 1 cylinder
« Reply #9 on: 08 March 2011, 08:56 »
There are loads of 8v's been broken on here and eGay so a cheap ECU isn't that hard to find.