I have an '01 XKR. Upon a full boost run from a dead stop to 60 or so and then back to about 20 we noticed a significant amount of blow by into the air box to the extent that smoke was billowing from the hood and passenger fender well. Under "sedate" driving no such problem manifests. In fact, the vehicle has plenty of power and uses no oil, doesn't smoke; nothing! A jaguar tech nearby opined that a common problem is leaking around the "O" rings while under full power. What "O" rings and where? I'm assuming he was referring to the partial tube. Oil separator on R valve cover is in place and orifice on L bank is unobstructed.

 

Have you opened up the airbox and seen oil stains on the filter element?


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