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Hi, First post here and its with a problem. Returning from cam belt change at local specialist and noticed the car running rough on a constant throttle and tick over not that steady. Returned the next day and they did a diagnostics check which showed :-
P0300 - Multiple cylinder misfire
P0301 - Misfire detected
P0303 - Ditto
P0304 - Ditto
P0302 - Ditto
P0441 - Incorrect Flow
Mechanic mentioned either a duff plug or coil but didn't mention the EVAP valve? have searched the net and checked the fuel cap, pipe work etc and all looks ok.
Could it just be a coincidence that the faults occurred while in their hands?
Replies appreciated.

Have been back in touch with the garage, boss wants it back in to try and sort it, suggested plugs to start as it hasn't had any despite being serviced every year, but cant find info on the mileage for a plug change? Coil packs were next on the list and I suggested the EVAP valve which he suggested could be forced by software. See how we get on when this virus allows us out.

That is annoying, I'd hope that they check the static timing first.

Plugs are due at the 4 year mark as is the air filter - there will also be a max mileage limit in there as well.

I'm surprised that you went for a belt change at the 5 year point, better safe than sorry I suppose, these 1.2TSI 16V engine's belt is meant to last longer than 5 years.

I agree, I'd suggest to first check the static timing of the cams and the fuel injector pump.

Too much of a coincidence:

More than one plug or coil pack failing at the same time especially with airflow errors.
More likely to be valve timing.

Do they mention which cylinders have misfires?

Brian422 wrote: Thu Mar 26, 2020 10:14 am Too much of a coincidence:

More than one plug or coil pack failing at the same time especially with airflow errors.
More likely to be valve timing.

Do they mention which cylinders have misfires?

I've not checked but I think if you check up on these misfiring numbers you would find they were for cyl1, cyl2, cyl3 and cyl4 - I've not checked just guessing.

iichel wrote: Thu Mar 26, 2020 10:10 am I agree, I'd suggest to first check the static timing of the cams and the fuel injector pump.

I'd guess that with a TSI engine - so a common fuel rail fuel supply system, the HP petrol pump will not be timed at all, just running flat out and sending excess fuel back to the tank - I could be wrong though.

You're right, I stand corrected.

Finally it's all sorted following the lockdown, turns out it was a vac line that hadn't been connected properly, must have been well hidden as I gave everything the once over.

Well that is good news, now at least you know that they did a proper job on the cambelt, one worry less!