ARES Tuning Limited

Another recommendation from Rtech!

Audi S3 8V misfiring severely on cylinder 2, this would get worse at the engine seen heat and particularly high in the rpm it would misfire

No codes or faults however! But not something I haven’t seen before..

Usual checks and data logging before the borescope came out and confirmed my suspison..

Carbon build up! Excessive burnt carbon - particularly on the exhaust valves, this is where his issue lay. We can see the valve seat has burnt and has uneven surface and colour across the seat as does the back of the sealing face of the valve, very deeply pitted seating face so these valves where for the bin

Just take a look at his top chain guide bolt though! Was nearly completely backed out! Lucky….

Head came off, stripped down, cleaned and skimmed, replacement exhaust valves lapped back in, intake valves cleaned back, new stem seals and all rebuilt.

New head gasket and head bolts, new vac pump gasket and the main drive timing chain replaced for good measure.

Complete with new direct injectors and we now have no misfires on idle or at the top!

They were in a bit of a state those exhaust valves! At some point this head has been replaced, lots of FIPG sealant on the rocker cover and a distinctive “X3” marker pen on the sealing face of the head

Anyways, back to Rtech she goes! 👌🏻😎

Tom’s track weapon came in to us with milky coolant!

We built this engine back in 2024, it has seen hundreds of laps at the ring, donnington and spar etc

He was sure the head gasket had failed, I was very sure it hadn’t - it sports ARP2000 head studs and we’ve never had or seen a failure, engine was running fine, no smoke or misfires

I was certain the issue was his oil cooler, but this oil cooler had only 2k miles

So a complete coolant strip down was done, his main radiator removed and 8 hot kettles flushed out the horrible milky residue - whenever oil contaminates the cooling system it is a bad day! It takes a considerable amount of time to ensure everything is flushed out

Oil cooler was removed and in the housing we found a crack on the gasket seat - and his oil cooler had of course failed

Didn’t end there though! His thermostat had unfortunately caught the brunt and was subsequently replaced

So! Oil and coolant sorted… he also complained of a gearbox fault as temps got towards 80c, this is typical of a failed mechatronic unable to hold pressure. Mech unit was cloned to a replacement and reinstalled to the gearbox with adaptations carried out

Now? It’s back ready for the track once again 💪🏻😎