Premium Gas


#1

I own a 2002 Nissan Maxima, V-6 3.5 engine. The manual recommends using premium gas but with gas so high, I’m wondering if it’s really necessary. Thanks.


#2

If the manual recommends premium, then I would use it. Have you actually done the math? Gas is just plain expensive no matter the grade (but only in comparison to what it used to be in the US), and if you checked you’d probably notice only relatively small savings.

You might try stepping down, but then you have to listen really carefully to the engine and go back up if you hear any kind of knocking or pinging (like the sound of marbles rattling around under the hood). Driving like that for a long time can damage the engine. The extra for premium will be cheaper.


#3

If a car is designed to run on premium (which yours is) then you’re NOT saving any money by using regular or plus. Does the owners manual say Premium is recommended or mandatory? If mandatory then do NOT use regular…it could damager your engine.


#4

The maxima has a knock sensor, so if you use regular gas, the engine computer will retard the ignition timing to avoid engine knock. This will reduce the engine performance and efficiency, and probably will not do any harm.

Keep an eye on you fuel economy and see if it drops.


#5

The knock sensor system will never fail? The engine can retard timing for any ocassion, and always retard enough? And, it doesn’t matter how old the car gets? That, is faith!


#6

Either way, it makes little sense to use less than premium. If there is a knock sensor and it works correctly, the 10cents a gallon saved at the pump is lost on performance & efficiency.


#7

Having sold Nisaans before I can tell you that you will not hurt anything if you use 87 octane, but you will lose fuel economy and about 15 HP. So it’s kind of a wash. The VQ was designed to run best on 91 octane or better. If you want to drive a nice higher end car. Then you should be able to afford to keep it on the road.


#8

I agree. While engine damage will be prevented (assuming the manual really says “recommended” and not “required”) the engine may not be operating at its optimum.

However, if the gas mileage is being carefully tracked and a few tankfulls of regular don’t affect the mileage at all, I’d accept that as evidence that the knock sensing system did not detect any preignition and did not have to make any compensating adjustments. That to me would make the use of regular an acceptable alternative. I’d also suggest continuing to carefully track the mileage for any changes.


#9

The meager $0.20-$0.25 killing you or maybe $3-4/fillup that is constant?

I find it interesting the price of fuel keeps going up but the price difference of regular vs premium has remained constant even back to the days when regular gas was $1.00 per gallon but my car required premium and its was $1.20/gallon.


#10

Failure of the knock sensor is a common problem on the older maximas. I have personally replaced them on a 1996 and 1998 model. The computer can tell if it is bad and permanently retard the timing until repairs are made.


#11

If you want to run your Maxima on regular gas, just drive it like a Sentra.


#12
It is recommended because if you don't use it your car will have less power and will use more gas, eliminating the savings you are looking for. 

I would be surprised if you started driving like a little old lady and continued to use premium your total fuel cost will be less that it was before the price went up (the last time).

#13

Your fuel tank holds 18.5 gallons. lets say that some how you managed to coast into the gas station with nothing left in your tank. You’ll spend $3.70 more for that tank than if you bought regular.


#14

Your fuel tank holds 18.5 gallons. lets say that some how you managed to coast into the gas
station with nothing left in your tank. You’ll spend $3.70 more for that tank than if you bought regular.

Here’s a quick back-of-the-envelope calculation:
With gas around $3.70/gallon, if the OP’s car gets around 18.5 miles/gallon, then a mileage decrease of 1 or more miles/gallon from using regular means it costing him more to fillup with regular.


#15

You have all that power and all those injectors and all that computer and you should use premium.