I own a 1994 RX7 with 38.5K miles. Until recently, its oil consumption has been minimal. However, since my last oil change, which was about 1500 miles ago, I've had to add two quarts of oil.

The car is not leaking oil, but I do notice some rather significant puffs of white smoke between shifts when I'm at full boost. Under normal driving conditions and at idle, I never see any excessive smoke coming out of the exhaust, nor do I smell burning oil.

One last data point to consider. I don't know how it happened, but somehow every cell in the ignition map for my leading plug was set to -25 degrees (Power FC). I'm not sure how long the car was running that way, but the map has since been reset. I also do not know if the car was actually running -25 degrees of leading timing, or if I was simply having a problem with the commander.

Any ideas?