I'm going through a quart of oil every 1k miles. There was some obvious leaking around and under the distributor, so I replaced the distributor O-ring and distributor shaft seal (there was a little oil in the distributor cap). This made no noticeable difference in the amount of oil I'm losing. I don't see signs of oil leaking from the valve cover gasket area. When I replaced the spark plugs, there was no oil in there, so it's not the spark plug grommets/seals. I've looked at the VTEC solenoid (viewed from top and side), but it's not very oily around there, though maybe I need to get under the car to see the backside of the engine to spot a leak from the solenoid? The funny thing is that I don't get oil spots on the ground under the engine. I would guess that if the rear main seal had a significant leak, I would see obvious oil spot on the ground. So this gives me hope that the leak won't be very expensive to fix (rear main seal will get done if I keep the car long enough to need to replace the clutch disc). Where I do see oil is on top of the transmission (manual trans) housing. Does that provide a clue as to where the oil could be coming from? My guess is that this oil comes off when the car is moving, resulting in the lack of an obvious oil spot on the ground when parked. What are the most common oil leak sources on these 6th Gen I4s apart from the dissy, valve cover, and VTEC solenoid?