I would check the condition of the spark plugs, and suggest a fuel system cleaning service. Those who use primarily 87 (lower octane) fuel have a higher chance of carbon build up in the fuel rails and build up on the injector heads causing an uneven spray pattern. You may want to service your fuel system, that may address your concern.
〉 Answered on Sep 27th, 2007 by Amanda J. Pierce, MBA "AJ", Certified Mechanic, Project Coordinator; Primavera Scheduler at VIGOR Alaska Industrial Shipyard & BizzM3ch Solutions
Fuel mileage down to 20 mpg, that must hurt.
Did the Maxima receive a tune-up at 30,000 miles.
If it didn
〉 Answered on Sep 27th, 2007 by Amy Mattinat, Owner and Author at Auto Craftsmen Ltd
If you haven
〉 Answered on Sep 27th, 2007 by Suzanne Grego, Technician at City of Philadelphia Fleet Management