Random misfires and rough idle

[Buddy Love]

Hi guys.

Posting here in the hope someone might be able to shine some light on my situation coz I'm running out of ideas and my cars still of the road.

About 2 months ago I broke down. CEL flashing and car felt awful. Pulled over, and the breakdown company arrived. Turned out to be misfires on cyl 1,5,6,7.

I had changed all spark plugs about 1 week prior to this, as well as all filters and fluids.

After the breakdown. I changed all 8 injectors and did a carbon clean. In spite of all of this, the car still has the same symptoms on the same cylinders. I've swapped coils/plugs round to see if the problem follows, cleared codes, even changed the battery as the battery weak warning kept coming up.

I know taking it to a garage, they will tell me its plugs/coils/injectors and try to charge me stupid money to change them, although they're all new anyway.

I then noticed the other day when moving the car off the ramp, that as the car revs above about 2000 rpm. The CEL goes off and the car seems to be OK. But still idles awfully.

Did a bit of research. Found it could be a potential pcv failure. Checked them. Seemed OK but had alot of carbon build up. And I tore a diaphragm when I dismantled one. Like a muppet. But I ran it up with the valves off, blanked off the intake part and let the crank breathe to atmosphere, made no difference. So unlikely to be them.

So now I'm kind of running out of options. If anyones experienced this or something similar. I'd massively appreciate any advice/ideas.

Thank you
Buddy

[Royclarke]

It was a different car but I chased a mis fire on my Audi s4 b8 for a year,it would go into limp mode every time I put of 1/4 throttle,it went to Audi and various other garages with out them finding it,I changed everything plugs,coils,sensors live logged it,pressure tested,smoke tested,everything and it turned out to be a bad Catalytic converter,the things is I bore scoped the cats and they looked ok apart from a little crack in one which I thought it couldn’t be that so didn’t think about it again for 6 months and a lot of money until it blew out,replace both and it was fixed,I don’t know if this will help but something to look into,easy to check just take the sensor out the cat and bore scope it,any damage at all they knacked,hope you sort it mate