MB21

@DaniP Pleased you've got it resolved. Now left me wondering whether the coil pack fix was incidental to the problem I experienced. I had suggested to them about checking the harmonic balancer, but they were adamant that it was fitted correctly. I wonder if in the process of refitting the cambelt they unknowingly corrected the positioning of the harmonic balancer / crankshaft pulley and also swapped the coil pack at the same time while the air intake was off. Car seems fine now, and I am convinced I am being overly sensitive about the remaining vibration.

@DaniP Sorry for the delay in replying - been away for a few days. My Fabia appears to be behaving itself since the change in coil pack and spark plugs. There is still a noticeable, but very faint, vibration - but this could have been there before the cambelt change, and I am probably only sensing it because I am looking for it. Before, the whole car was shaking at c. 1,200 revs with the car stationary and in neutral. Just to be clear, it was only 1 of the 3 coil packs (that sit on each of the spark plugs) that was found to be at fault on my car. Did your garage check / swap out all 3 on your car? Hope your garage get it sorted soon - will be interested to hear how it pans out.

@DaniPI can't see a link between a cambelt change and a coil pack failure. The coil pack had evidently been failing for a while, given the colouration on the spark plug, so why we weren't experiencing vibration before the service - I don't know. Perhaps the previous cambelt / tensioner / roller was better at absorbing the vibration? I honestly don't know. I suppose there is an outside chance that the coil was knocked during the cambelt service, which resulted in the failure. The good news is that it is very easy to check, and should take your garage only 30 minutes to whip the air filter housing off, and check each of the spark plugs. I wouldn't rely on a diagnostic tool, as it didn't show up on my car. My garage, I feel, have been very fair - why I like a good independent. Despite spending hours refitting the cambelt (twice) to check they hadn't made any mistakes, they only charged me for the new coil and a set of spark plugs and have absorbed the labour. Will be interested to hear how you get on next week - fingers crossed!

I have got the car back from the garage now. They believe it was a faulty coil pack on one of the spark plugs. They've replaced the offending coil pack and all the spark plugs - they were only replaced last year, but made sense to do them all at the same time. The one spark plug was discoloured on the body in comparison to the other two. The error wasn't showing up on the diagnostics, but it could have been within the software tolerances 🤔 The vibration is significantly improved, but it is still just about noticeable at around 1200 revs. However, I have little to compare it against. We've agreed that I will drive the car for a while and see how it goes. They are confident that the timing is spot on. @DaniP They don't routinely source their parts from VAG, but ensure they only use reputable manufacturers. I had wondered whether it could be a manufacturing fault, but I suspect it's unlikely given the number of these being manufactured by different companies for VAG. It would be useful to know from anyone running a 1.0Tsi with the original cambelt whether there is any noticeable vibration from the engine around 1100 - 1200 revs. I'll keep you posted on how I get on. But thanks everyone for your contributions.

I was hoping that I could come back with some positive news, but the garage are still working on it. They've refitted the cambelt having carefully gone through everything, and put it back together, but still getting the same result. They maintain they do 2 or 3 of these every week, and not previously encountered the problem. They recognise there is a problem, and accept that it is likely to have been caused by the cambelt replacement. I'm hoping to hear again in the morning, and will keep you posted. I saw @Twiz had a similar issue, and concluded it was the harmonic balancer had been refitted incorrectly. I've highlighted this to the garage, but they weren't convinced. I assume this isn't replaced as part of the cambelt kit? Also saw that @toot and @ForCar40 posted a link from mechanic expert on the Mk7 Golf timing belt replacement - the link is no longer live. I don't suppose anyone else has a copy / live link that I can access? Thanks all for your help.

@toot Sorry for my omissions. The car has been serviced in line with the Skoda recommendations, and hence the decision to replace the cambelt this year even though it has only covered 36,000 miles. A full service and brake fluid change was carried out at the same time.The spark plugs were replaced last year. The air filter hasn't been replaced, but based on your helpful schedule will be on the list next year. The vibration has definitely arisen following this service, and hence my belief it is related to the cambelt change.

@DaniP @ForCar40How did you get on with your respective garages following your problematic cambelt changes? Any resolution? I had my cambelt replaced earlier this week by my trusted and long time used indie. I also have a 1.0TSI 2018 Mk III and like you, now have a noticeable vibration starting at c. 1100 revs. The vibration remains when driving, but less noticeable. They have had a quick look and couldn't see anything obviously wrong, but agree the vibration is very noticeable and not normal. The car is going back in on Monday for further investigation. They didn't think it would be a timing issue, as they believe the EML would be showing almost immediately. The car has only done a few miles since the service, so not sure how long it takes for the car to register an issue. If you have got yours resolved, would be grateful for any insights - will be helpful to point the garage in the right direction. Thanks