I have a 91 civic hatch std with DPFI. I changed my oil cause the oil light came on a couple times. after bout 2 weeks and like 800 miles it came on again. i checked my oil level and it was 2 qts low. theres no aparent leakage under the car when i park it. could it be burning that much oil? i mean the car runs great and the odor coming from the exhaust smells typical.