Been using 87 octane in '02 maxima for 1yr. have replaced oxy & nkock sensors. Is this due to low octane?

87 unless you have a high performance car. It's really unnecessary to use anything above 87. They've done many study shows and tests and show no different results between the 3

87 octane--this least expensive one

If it has a lot of carbon & other problems
try 89 octane if it knocks

According to page 10-3 of the 2001 Nissan Maxima Owner's Manual:

FUEL RECOMMENDATION
Unleaded premium gasoline with an octane
rating of at least 91 AKI (Anti-Knock Index)
number (Research octane number 96)
If unleaded premium gasoline is not available,
unleaded regular gasoline with an
octane rating of at least 87 AKI (Research
octane number 91) can be used.
However, for maximum vehicle performance,
the use of unleaded premium gasoline
is recommended.

Engine "knock" is not just an unusual sound - but over time can cause real damage to the engine. You *should* use fuels with the recommended octane levels, but if you choose to use fuel with a lower octane level due to reduce fuel costs - do not repeatedly use fuel that causes engine knock. Find the "sweet spot" between the cost of lower octane fuel and an octane level that does not cause knocking. Expect fuel economy and performance to drop with lower octane fuels, too.

Good luck!

sounds like a bad idle control sensor, most garages charge $75.00 for a diagnostic, the sensor is about $45.00 it could also be a bad fuel filter,have you been burning 87 octane fuel?[cheapest fuel] ethanol fuel is'nt good for your v.w. at least try to use 89 0ctane but no ethanol fuel!! you can use 87 octaneBUT you need to add octane booster with it, which you can get at the dollar general,wal-mart,k-mart,auto zone,advance auto it's really an economy thing though. what ever your budget is, i have a 87 toyota van and use it every day for qa mechanic svc. i buy 89 octane fuel,i've bought 87 octane and everytime i have,i've had to replace the fuel filter. merry christmas!! and as always, if you need further assistance please repost your question and an expert will be happy to assist you!!

Usually an indication of Bad fuel, needs a tune up or Slipped Timing. Most likely bad fuel or tune up depending on when the last time you replaced the plugs and wires was. If you have been using the 87 Octane low grade fuel that would cause this or if you happened to get some bad fuel at a station. The vehicle will run on 87 octane but was designed to have a minimum of 89 octane fuel, the mid grade. If you haven't replaced your spark plugs in the last 25,000 miles replace the spark plugs and wires. If you suspect the fuel is the issue you can get injector cleaner or Octane boost and add to a FULL tank of gas to clean it out.

Run the regular low octane (87) as the truck is computer controlled & the higher octane fuel burns slower & older cars with adjustable timing benefit with the slower burning fuel because the timing can be advanced further, but the computer controlled cars also control timing, so the more expensive gas is wasted & could cause emission problems down the road due to unburnt fuel running through the cat. & rest of pollution controls. If the vehicle detinates or pings when driven then run the higher octane fuel & run injector cleaner through to clean up the fuel system. Lucas is the best that I have used.

87 octane is just fine for this vehicle, unless you live in a very high altitude location, in which case you may need to run 91 octane.

This should be stated in you owner's manual. Most cars are fine on 87 octane. Some high performance engines will give more power with higher octane fuel.

check the detonation sensor.and low octane gas .if running 87 add a little 89 octane to see how it work .dont put 92 in it it will cause it to run horrible. check your manual to see what octane your car run better with.

Regular unleaded (87 octane) is the correct grade.