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:D Hey, I just bought my Nissan Murano SL AWD. What kind of gasoline do u put premium or regular. How about the break in period of this SUV, how fast can i go till 1200 miles. Thanks. :?:
 

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Gasoline

I've used Regular (87), mid-grade (89) and Premium (91) in my Murano and have found a small increase in gas milage with the higher grades, no real difference between mid and premium, I'm not sure it's worth the price difference. As far as break-in, you shouldn't go over 4000 rpm for the first 1200 miles.
 

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I use the premium in the Murano.

My supercharged Grand Prix doesn't like lower grade fuel so I got in the habit of using premium gas. The few times that I tried a lower grade, my fuel economy went down and the car bogged a couple of times.

As for the MO, I think she's worth the extra .10 a gallon. You gotta figure that if only cost you $2 more for a $20 stop versus getting lower MPG with the regular unleaded, then you pretty much break even. Not to mention the whole" cleaner gas " thing.

Just my .02 :lol:
 

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I prefer to use Premium from whatever station I visit, usually Amoco or Texaco.

Twice, I've accidentally had the attendant put a few gallons of Regular in it only to follow up with Premium after I noticed my mistake. I drove an Exploder for maaaany years, using Regular, so I haven't broken my habit :p
 

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91 :D
 

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The VQ needs premium. It's a high compression engine. Any lower and you may get engine knock (detonation)... that is a very bad thing. We only run premium in both our Murano SL and Maxima SE (they both have VQ engines). :roadtrip:
 

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used 87, 89 and 91. Did not really notice difference. But than again i did not push the engine yet.
 

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you shouldn't really switch gasoline types, mixing is bad!!!! stick to what it says in the manual which is premium 91 and dont go lower than that!!
 

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Enforcer said:
The VQ35DE is a 10.3:1 high compression ratio engine. High CR engines perform better and last longer if you run high octane. Yes the engine has a knock sensor and the computer will retard timing to prevent engine damage due to knock. But there is a lot more going on than just knock.
So true!

For anyone who may not know:
The higher the octane, the higher the resistance for spark knock, or "pinging". Pinging is usually caused by the fuel igniting prematurely. What happens is the fuel ignites before the spark plug fires, it ignites on it's own because of the high compression. You have an explosion taking place on one side of the cylinder, and the plug firing off, sending a different explosion in it's direction. These two "explosions" collide causing the knocking sound. This is very bad for an engine. It is more prone to happen under a heavy load, such as accelerating. As Enforcer said, there are knock sensors to help prevent damage, but why risk it?

BTW, you sometimes hear that older cars might start needing higher octane fuel if they start to knock. Usually this is because of carbon build up in the cylinders. The build up will increase the compression ratio, and decrease the cooling.
 

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If using lower octane fuel "damages" the engine as some have implied, why then does the manual state on page 9-3 under FUEL RECOMMENDATION:

"Use unleaded fuel with an octane rating of at least 87 AKI.... For improved vehicle performance, NISSAN recommends the use on unleaded premium gasoline with an octane rating of at least 91..."

To me it sounds like Nissan isn't dissuading people from using regular unleaded, much less indicating that it may be potentially harmful to the engine, but rather implies only "improved performance" (whatever that means-- acceleration? gas mileage?) if you use premium instead...

Additionally, www.fueleconomy.gov (http://www.fueleconomy.gov/feg/noframes/19221.shtml) which was set up by the Dept of Energy and the EPA lists the Murano as using "regular" unleaded gasoline.. go figure...

just my 2 cents.
 

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Good question, I asked that of my dealer and all I got was the "yeah your right, that doesn't make sense". Keep in mind the 350Z manual says 91 minimum and the engine is the SAME.

As far as damage, the knock sensor prevents the most serious damage. Long term, say 100,000 miles or so, that's a different issue. In other words, Not a big issue as far as the Nissan warranty coverage is concerned. The knock sensor detects knock and then the ECU retards timing. In other words, it has to knock first. So you don't prevent knock absolutely, you just prevent it from recurring for a short period of time. Don't know how short.
 

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Well they're based on the same engine but they're definitely not the exact same as the 350Z has a maximun horsepower of 287 @ 6200 rpm and a maximum torque (lb-ft) of 274 @ 4800 rpm -- I could see why they would only recommend premium in that bad boy!

(Wouldn't it be cool if the Murano did have the same engine! --- Of course then it would be called an FX35...)
 

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I wonder how long it takes for the MO to advance the timing if you put in higher octane fuel? That's assuming you run the tank almost dry so there's little mixing of the two.
 

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Enforcer, good read. This quote from that article explains what I was trying to say:
------Quote------
Why do we need Octane Ratings?

To obtain the maximum energy from the gasoline, the compressed fuel-air
mixture inside the combustion chamber needs to burn evenly, propagating out
from the spark plug until all the fuel is consumed. This would deliver an
optimum power stroke. In real life, a series of pre-flame reactions will
occur in the unburnt "end gases" in the combustion chamber before the flame
front arrives. If these reactions form molecules or species that can
autoignite before the flame front arrives, knock will occur [21,22].

Simply put, the octane rating of the fuel reflects the ability of the
unburnt end gases to resist spontaneous autoignition under the engine test
conditions used. If autoignition occurs, it results in an extremely rapid
pressure rise, as both the desired spark-initiated flame front, and the
undesired autoignited end gas flames are expanding. The combined pressure
peak arrives slightly ahead of the normal operating pressure peak, leading
to a loss of power and eventual overheating. The end gas pressure waves are
superimposed on the main pressure wave, leading to a sawtooth pattern of
pressure oscillations that create the "knocking" sound.
---------quote---------



twelsh said:
Well they're based on the same engine but they're definitely not the exact same as the 350Z has a maximun horsepower of 287 @ 6200 rpm and a maximum torque (lb-ft) of 274 @ 4800 rpm -- I could see why they would only recommend premium in that bad boy!

(Wouldn't it be cool if the Murano did have the same engine! --- Of course then it would be called an FX35...)
I don't know what is the CR of the Z car. It might be the same engine, but a different computer, and intake/exhaust design. The hp difference could be from a more aggresive fuel/timing curve, which would demand high octane fuel. Some power difference could also be the size and design of the intake runners and exhaust system.
 

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In my 97 Maxima, I had a knock sensor go bad after around 80,000 miles. This was after using premium for the life of the car. From what I understand, a bad knock sensor would default the computer into low octane mode to protect the engine. I will continue to use premium in the Murano, but I still think Nissan knock sensors are pretty poor quality.
 
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