Well, I think I am taking my car in. I have used 2.5 qts/2000 miles.
On my other car, it is normal to use up to 1 qt every 800 miles. On the Z, I called the dealer and they said they do not know the norm. The service department did say that over 2 qts is a lot more than what they wanted to hear.
Worst case scenario, If (and "if") they need to replace the engine (due to rings, or what-have-yah), what do you guys think? I just don't trust the dealer putting a new engine and some mechanic ends up doing short cuts (e.g., a washer, nut, bolt, or so being not re-installed). I guess getting a brand new replacement is out of the question?
