Which engine cylinder is No. 4 on the RS4?

[Golich]

Vag Com is telling me I have a missfire on cylinder No. 4.

I don't have any info on which cylinder is which.

Reluctant to buy and down load Erwin ignition manual for this. The bloody engine manual simply tells you the firing order.

I guess I could diconnect each coil pack in turn but that's a last resort!

[Golich]

Its ok I found out by disconnecting the coil.

FYI looking from the front of the car into the engine bay. Cylinder No. 4 is the cylinder closest the front of the car on the right bank (passenger side on RHD car.) with 6 being the furthest away. As defined by VAGCOM.

Swapped the coils and plugs around to see which is causing the reported misfire. It didn't make any difference!

The thing is you'd be hard pushed to notice the miss. Its not noticable when driving just a ever so slight sporadic judder while its idling.

The odd thing is VAGCOM sometimes records a missfire on cylinders 2 and 3 and sometimes 6. But this is very rare. Yet all the plugs look a nice tan colour and the car seems to be running fine.

I had the trial REVO software last Nov. I'm wondering if the new map from that has anything to do with this? Any ideas?

[PhilT]

I've known VAGCOM report misfires, but it was resolved by changing the plugs. When did you last change your plugs?

[Golich]

They were replaced at 38K miles now at 52K miles therefore 14K miles ago. I'm sure these £63 plugs are good for at least 20K miles? Like I say I swapped plugs around but No. 4 consistently records a misfire.

I read a few interesting posts on the Yahoo VAGCOM site of this being a common problem with the 2.7 engine. One American guy solved his problem by what I assume is injector cleaner or some kind of Redex type stuff as he adds it to the tank every service. Another had the idle turned up!

I'm going to get it booked into Star Performance for a rolling road health check. The last time it was there the EGTs were playing up and I was 80bhp down but the torque was 20ftlbs up on standard and I didn't even notice the power was down. The only indication the EGTs were playing up was the car noticeably missing over 5k RPM. Since replacing the EGTs the car seems to be running fine.

Does anyone know how VAGCOM

[Golich]

I meant to continue, does anyone know how VAGCOM is able to record a misfire. I see three wires going into the coil pack. Is one of these a diagnostic?