Mk4 Golf GTI 1.8t misfire
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Discussion

2 GKC

Original Poster:

2,303 posts

133 months

Sunday 15th February
quotequote all
We have had this car in the family since it was a year old. Took it to a garage for a timing belt and after it came back it was misfiring. It went back to the garage and they couldn’t find a problem, said timing was spot on.
Been to two other garages since who agreed the timing is ok. One then did all four coil packs, which made no difference.

The misfire seems to be worse from warm starts and is generally at low revs. Car still has plenty of power when not misfiring.

At a bit of a loss what to do. The last (VW specialist) garage said he would have to start taking the engine apart at great cost because he had checked all the obvious stuff.

It’s too good to scrap (80k miles)

Any one had this and or got any recommendations please?

Belle427

11,796 posts

261 months

Sunday 15th February
quotequote all
So if it were fine pre belt change my suspicious mind is telling me something they have done has caused it whatever that may be.
Does the car log any fault codes?

2 GKC

Original Poster:

2,303 posts

133 months

Sunday 15th February
quotequote all
No apparently not. It’s a misfire on one cylinder only.

bangerhoarder

784 posts

96 months

Sunday 15th February
quotequote all
Plugs done with coilpacks? I had this on an S3 and it was just a dead plug.

thebraketester

15,723 posts

166 months

Sunday 15th February
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Plugs? Compression test?

Dr G

15,940 posts

270 months

Wednesday 18th February
quotequote all
2 GKC said:
No apparently not. It s a misfire on one cylinder only.
No codes for a misfire? Not unless someone has been playing funny buggers with ECU.

Is the misfire consistent? Swap plug from 1-4 and see if it moves the misfire with it. Injector test depending on what fuelling looks like, should be able to see what they're doing through diagnostics.

Where in the country are you?

bangerhoarder

784 posts

96 months

Wednesday 18th February
quotequote all
I've never had much luck with these throwing codes for misfires. May be the generation of the systems. I've not had injector issues though, which could log a code.

catso

16,317 posts

295 months

Wednesday 18th February
quotequote all
Dr G said:
No codes for a misfire? Not unless someone has been playing funny buggers with ECU.
It should definitely give a code and even a description of which cylinder. My S4 had an intermittent misfire, would only do it under full throttle and when it did, it would disable the cylinder and run really rough until engine off/back on.

VCDS clearly told me Cylinder 5 misfire, a new coilpack fixed it.

Even my Son's old 2004 Polo gave me a Cylinder 3 misfire when a coilpack failed, so I don't believe a Golf doesn't.

2 GKC

Original Poster:

2,303 posts

133 months

Wednesday 18th February
quotequote all
Dr G said:
No codes for a misfire? Not unless someone has been playing funny buggers with ECU.

Is the misfire consistent? Swap plug from 1-4 and see if it moves the misfire with it. Injector test depending on what fuelling looks like, should be able to see what they're doing through diagnostics.

Where in the country are you?
Bristol area. The garages all seem mystified by it. It’s not really consistent, from cold start it takes a while to appear and tends to be at low revs but can be really bad, shaking the car

CSR Performance

637 posts

16 months

Wednesday 18th February
quotequote all
All of the things mentioned in this thread so far could be the issue.

Did the other 2 garages check the timing properly with a locking tool?

Can you get the codes read by someone with VCDS or a proper diagnostic setup? As said above, it will almost certainly have a code logged. Then you can switch plugs and coils around to try and understand where the fault is.

The N75 can be a culprit but its impossible to say without seeing the car.

Depending on where you are in the country there are a number of renowned VAG specialists. My personal preference is Stealth Racing in Southam.

Dr G

15,940 posts

270 months

Thursday 19th February
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Try RS Autotechnik; I don't know them personally but have had multiple customers tell me how pleased they were with service and work done. They're Audi guys but that engine went in plenty of 4-ringed cars too.

Peter T

159 posts

268 months

Thursday 19th February
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Are you sure that it is miss firing? Lumpy running can sometimes cloud the same issue. I have seen this many times and there are quite a few issues that give this feeling. One issue i found was a fuel pressure sensor when hot gave erratic parameters to the ECU which caused rough running for a few seconds on start up. Another was a leaking injector which caused a cylinder to run rough for several seconds also, both did not generate a fault code and cleared after some time and engine ran great, took a while to figure the cause.

2 GKC

Original Poster:

2,303 posts

133 months

Thursday 6th August
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Going to sell as spares or repairs. Any thoughts on how much to sell it for? £500?

Belle427

11,796 posts

261 months

Friday 7th August
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Has to be worth that to someone, maybe start it at £1000 as your going to be hit with offers anyway.
You would need to find someone capable of doing proper diagnostics to stand a chance of fixing it, scoping injector pulse and ignition coils for example to see what might be responsible.

ManicMunky

698 posts

148 months

Friday 7th August
quotequote all
2 GKC said:
Going to sell as spares or repairs. Any thoughts on how much to sell it for? £500?
Any more details?

2 GKC

Original Poster:

2,303 posts

133 months

Friday 7th August
quotequote all
Silver, three door, V plate. Car has been in our family since around 2000 and garaged since about 2003 when my mum bought it at the end of my company car lease on it. So it’s 2 owners being the lease company and my mum. 81k miles and MOT expires 17 November.
Has been parked up in the garage since February and is currently SORN.
Irritatingly, we can’t find the service history at the moment but I reckon I’ll find it before it does go for sale.
It was running beautifully til this bloody garage did the timing belt and always felt faster than 150bhp ought to have done. New coil packs were fitted by another garage who tried to fix the issue.