A3 (2001) 1.6 running on 3, blowing smoke .. fouling plugs?

[dcskinx]

Hi just after some advice on my A3 Audi with the 1.6 AVU engine. When I first brought it I had a bit of a fan/overheating problem, I found the cause of overheating to be the electronic thermostat (thanks to this forum), so replaced this with a new one and whilst at it replaced the temp sensor.. This fixed the overheating problem. Took it for a drive, quickly realized it was running on 3 cylinders, put a new set of plugs in it and seemed to run well even though it blew quite a bit of smoke (black / grey) and spat out a big amount of what looks like black spray paint out of the exhaust.. And then started running on 3 cylinders again. Pulled the plugs out and they all looked very black. Plugged the VAG cable in and pulled the faults, which gave me misfires on 2 different cylinders, O2 sensor malfunction, and one to do with the EGR valve.. Actual codes listed below. The car puffs out a bit of smoke on first start, but runs on 3 and looks like its running very rich, puts out a lot of black smoke when revved.. My main question is, does anyone know what I should look at next? Should replacing the EGR and O2 sensor make much difference? Can I simply remove the EGR setup buy buying the blanks from eBay ? If worse comes to worse, can I replace a AVU engine with a AKL 1.6? Thanks for reading my first post, any help would be much appreciated..

Fault codes are as follows;

- 16685
- 16514
- 17811
- 16514
- 16514
- 16686

Also, here is a video of the 'black paint' type stuff that blows from exhaust

A3 exhaust test - YouTube

And another video of smoke blowing on first start up

A3 test #1 - YouTube

 

[Spatula]

Have you tried switching coil packs over? i.e. 1 with 2 and 3 with 4. Unplug battery for 20mins and reconnect. Run car and take another VAG reading. See if misfires have changed cylinders. If so, replace coil packs.

 

[Vex182]

I think your engine uses ht leads? Have you checked them for damage?