Audi A3 sline 2.0tfsi missfire/stutter @ 3k & 4Krpm

[skypeller]

Hi all

Got a missfire/hesitation about 3000rpm and another about 4000rpM only seem noticeable in 3rd & 4th probably mostly because you’re still commonly in reasonably speed in those gears perhaps. Car gradually got worse over the last couple months when it started doing this I assumed it was traction control intervening until it was more and more irritating I read the engine OBD codes to find fuel pressure fault code, random missfire code 0300 and each time I scan a different cylinder is listed. changed the fuel filter for new Bosch one, in tank pump (2nd hand genuine) and cam follower for new genuine, new low pressure fuel switch,also changed pump module for pattern and reset the codes - no further fuel codes ....
but still the misfire code 0300 followed by any of the cylinders most commonly cylinders 1&2

When I unplug the maf (tried cleaning with wd40 contact cleaner- fast drying) the car runs great not misfire as mentioned above .... no hiccups ... but I’m told that could be that the maf is actually ok and just masking the issue elsewhere.

Looking for some ideas incase suspected MAF doesn’t fix the issue.
Also ordered some ngk bkr8eix x4 which I will fit mid week when they arrive.
Plugs were changed approx 5k miles ago. Coils replaced with Bosch about 40k ago/ 3 to 4 years.
Cambelt was done around a year ago.
Stage 1 since before I bought it. Generally very well maintained car.
Gets to temp fine, doesn’t use water or oil.
Pcv appears to be a replacement at some point, also appears to have had walnut blasting at some point.
I’ve looked for vac leaks briefly but I know the engine bay quite well and it’s all in good shape really.

Car has 3 month old ‘cold air’ intake made by RAMAIR.

[Crafty_]

Take the ramair thing off and if you can the remap.

Gap the plugs correctly.

Compression test.

Edited by Crafty_ on Monday 12th October 11:57

[skypeller]

Another point to Make is that it only missfires at full throttle or near to full throttle otherwise it’s seemless

[skypeller]

Another point to Make is that it only missfires at full throttle or near to full throttle otherwise it’s seemless

[skypeller]

Another point to Make is that it only missfires at full throttle or near to full throttle otherwise it’s seemless

[skypeller]

Another point to Make is that it only missfires at full throttle or near to full throttle otherwise it’s seemless

[The Cardinal]

I had similar issues with a 2007 2.0T and it was resolved by replacing the charcoal canister and PCV.

[skypeller]

Resolved the issue - did a compression check & all was good.
Checked all the vacuum lines and they were fine as suspected.
New plugs arrived so I gapped them despite what the plug manufactures say on iridium / double platinum plugs and all is now perfect again!
Set the gap to 0.7mm as aposed to the standard 1.0mm gap. Seeing as it’s stage 1 I think the spark was struggling under chamber pressure at higher revs.