HI.
I have a problem with missfires on a Volvo S60 R machine.
It runs with VAG 115 coils and it runt fine upp till 1.6 bars off boost. 420bhp.
But when it boost more, up to 1.8 bar, it starts to studder, one or more cylinders missfires.
We run NGK BCP7RES plugs, with 0.5mm gap. The coils are all new, and ao is the plugs. The injectors have been checked for flow and were within 5%. The compression os also good on all cylinders.
And the problem only appears on full load on 4th and 5th gear at max tourque.
My suspission is that because we run on 4 stepper outputs, the 5th coil runs on a logic output this might be the problem.
And my question is, could a to low pull-up be the problem?
How much do the VAG115F coils need to give good opperation?
/Thorbjörn