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misfire cylinder 1........Cupra

Apr 1, 2014
862
1
'up anley duck'
Hi guys i need i little help regarding my mk2 cupra. I have developed a misfire on cylinder 1, there was alot of water on the coil pack/spark plug in cylinder 2 and 4 i've cleaned all of them up and swapped them around but there is still a misfire on cylinder 1. any help would be great.
 
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goldie87

Active Member
Nov 20, 2010
319
0
Midlands
I had a similar problem last week.. car started to misfire, bringing up the PO301 cylinder 1 misfire code.. took the coilpack out of cylinder 1 and it was rusted to hell :

34t613l.jpg


I also found that the area was filled with water, drained it out and replaced the coil pack and it sorted my problem out.

Just not sure why it was filled with water in the first place??
 

Tfsi_Mike

Active Member
Aug 30, 2007
2,386
6
Doncaster / Germany (Army)
I had the same issue. Moving coils & plugs around didnt move the missfire. Steadily counted missfires at idle. Could hear the odd hicuup from the exhaust at idle. gradually got worse.

New injector and it was right spot on then. Mine was cylinder 3
 
Apr 1, 2014
862
1
'up anley duck'
i hope its just an injector tbh mike, ive been hearing horror stories of melted pistons and destroyed engines due to misfires.

going do a compression test first just incase any damage has been done.

does anybody know the ideal compression for each cylinder.
 
Last edited:
Apr 1, 2014
862
1
'up anley duck'
ALL SORTED YAYYYYY.

compression test came back all clear
around 160+ psi on all cylinders.

took the inlet manifold off cleaned all valves and flaps also cleaned all injector plugs, removed all injectors cleaned them up using carb cleaner then resealed them.

put it all back together

jobs a gud un no more misfires.
 

Dan FR

Meth addict. Stage 2+ Yo!
Nov 14, 2013
1,684
8
Caerdydd
So the million dollar question is.....

What was the actual cause? how much build up did you have on the valves?
 
Apr 1, 2014
862
1
'up anley duck'
the injector plug on cylinder 1 was rusty. so cleaned it all off.

the valves were not that dirty tbh, not as bad a some cars ive seen, i think its been done before.
 
Apr 7, 2023
5
0
Scotland
Hi , am sure I seen something to dove water in coil 1 even afer replaced coil & removed bonnet insulation to do with bonnet strip can anyone hlp plz