Engine Performance problem
1997 Other Nissan Models 4 cyl Front Wheel Drive Automatic 90000 miles
----------------------------------------------------------------
Hi,
I drive a 1997 Nissan 200SX SE-R (the 2.0-liter version). I have a question regarding general maintenance, specifically related to gas mileage. My fuel efficiency has decreased in recent months. The car is well-maintained and has otherwise been running fine. Oil is changed regularly, tire pressure is checked frequently, and the car does not stall or have any other noticeable problems. However it has been a while since the car had a general tune-up (1 or 2 years). As a fairly inexperienced car mechanic but with some natural affinity, what can I do myself to check up and tune up the car's performance, and specifically its fuel efficiency? Replace the spark plugs? Clean, check, or replace any specific engine parts?
Thanks,
Devon Biggerstaff

You can do almost all the maintenance yourself. If your mileage has decreased, the first thing that I would be doing is tune-up. You can replace your own spark plugs NGK BKR6E-11 (set the gap at .044"), wires, distributor cap and rotor. Next is the filters (air, fuel and PCV valve).

While you are at it, if the front O2 sensor (the one by the exhaust manifold) has never been replaced, you may want to consider replacing it.

Next time, ask your questions under Sentra forum. That is the one that I normally respond to.