question on which gas to run.
 

ok so i picked up a 02 nissan sentra ser spec v last night. the owners maunal says to run no lower than 87 octane in the tank..what im wondering is would it be better to run higher octane?

i joined a sentra forum and they say you have to run higher octane..but i want help i know i can trust. some of the guys on the forum seem like typical ricers and just think high octane means mor hp lol..

i want to know if it is just better to run higher octane or not. thanks

Run 87, you'll be fine.

An '02 might be able to gain some advantage in peak HP with higher octane, but that wouldn't do you much good in regular driving.

I can't tell any difference in running in our '01 Lexus--it says 91 only, but runs the same with 87. Engine management takes care of the difference.

Also, all grades of gas now have the detergents needed to keep fuel injectors clean, a change over 20 or so years ago.

ok thats what i was thinking.. thanks for the imput..

if it runs good on 87,keep using it. higher octane fuel will only make your wallet lighter unless you are running a high performance engine.

well i re read the manual and it says only to used 87 when anything higher isnt availible..but it is technically a high performance motor

If your car is in normal condition it should run fine on 87 and the computer should adjust for slight differences. I assume a spec V engine is designed to run fine when in good condition with 87 per the manual.

But, with the miles yours has, MAYBE you might have a carbon build up which MIGHT increase the octane requirement. So let your ear tell you. If you hear a slight ping under heavy load you might consider upping the octane, just buy gas not the octane in a can, costs too much per "point". If the car pings heavily or worse, knocks, then you really need higher octane or there may be a mechanical issue to resolve.

Usually pings become more noticable or frequent in hot weather and heavy engine load(like hills)

The difference between pings, knocks and detonation have books written on them, even on our website. If you know what they are, then use your ear.

Good Luck,

Jim Henderson

jim..thanks yeah after reading the manual a little more it states only to use 87 when nothing else is availible and only put in a few gallons until you can find higher octane..i havent noticed any pinging yet.. but i havent been driving it too hard either, especially since it just threw a cat code...time to gut the pre cat and the cat..

i was already planning on doing it just not this soon lol

Since this wasn't metioned.... More than likely your engine has knock sensor(s). If it detects a ping or knock it will retard the timing a bit, doesn't matter what fuel grade you use. The higher octane slower burning fuel will allow more timing advance and more HP. So if you use a lower octane it will prolly just have a bit less power. Interesting how alot of engines say around 15 years ago required premium (Cad Northstar, honda V6 to name 2) that no longer require that.

Good God, Micah!!!!!!!!........With gas at the price it is, run it on the cheapest rot-gut 87 you can buy, it will make no difference to it.

FYI Pinging sounds like marbles being shaken in a can during acceleration. May be worse at part throttle and less at full throttle. If you hear that then go to a higher grade or adjust your driving habits to avoid ping.

Modern engines will pretty much run as much spark timing as possible without knocking. So in your case, running higher grade gas will yield more performance, since the computer will be able to run more timing advance before it detects knock.

The Northstar, another GM lemon, has been out of production for a long time. Current Cadillac engines are completely different. For example, direct injection makes a huge difference in detonation resistance. I also doubt if Honda is building the same V-6 that it did back then. What some newer Honda engines do to run 87 at 10.5:1 compression, in addition to the computer programming, is a small bore, long stroke, different combustion chamber shape and, in some cases, dual spark plugs.

Since too much spark advance leads to higher emissions, most engines are not programmed to advance beyond the limits of 87, some are, and that is listed in the owners manual.

true dave however the car does get over 30mpgs...which is way better than my 85 lol..so the extra money isnt that bad..




yeah i know what pinging is..and it does slightly ping under full throttle but not horribly.. i will be switching over to premium tonight since i need to fill-er up