car runs fine on 87?

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My car's owner's manual states that 91 octane fuel is recommended (not required). So I was curious this last time I filled up and put in 87 octane with 2.5 oz of TC-W3. I was expecting a good amount of power loss and knocking, because that's what people on the Maxima board say they experience using regular in a VQ35. But so far I can't feel a noticeable loss of power and I don't think it is any louder. I don't know what knocking sounds like though. So far I have 55 miles on the tank and gas mileage seems to be close to when I use premium, but I won't know for sure until the next fill up. The car has a knock sensor so I guess it's doing its job. Am I just not sensitive enough to these things or is my car working fine on 87?
 
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You`ll know it if your car specs premium and you put in regular. I tried it once on my old 300ZX turbo (only about 5 gallons or so on an empty tank) and it wouldn`t even hardly make it up a hill. Was clattering and knocking so bad it scared the heck out of me. I did an immediate u-turn and filled it all the way up with premium. No more knocking :^)
 
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 Originally Posted By: asiancivicmaniac
My car's owner's manual states that 91 octane fuel is recommended (not required). So I was curious this last time I filled up and put in 87 octane with 2.5 oz of TC-W3. I was expecting a good amount of power loss and knocking, because that's what people on the Maxima board say they experience using regular in a VQ35. But so far I can't feel a noticeable loss of power and I don't think it is any louder. I don't know what knocking sounds like though. So far I have 55 miles on the tank and gas mileage seems to be close to when I use premium, but I won't know for sure until the next fill up. The car has a knock sensor so I guess it's doing its job. Am I just not sensitive enough to these things or is my car working fine on 87?
The same recommendation here. For extra power use 91 or higher octane. We tried 93 octane for awhile and went back to using regular 87 octane. Could not tell the difference in power or economy. Did not push the vehicles to their extremes but for everyday driving could not tell any difference and saved some money in the process.
 
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per mile cost is lower with 91 gas. lower octane lower power lower mpg. when gas is $3 a gal, make good sense to higher, % gain in mpg exceeds % gain in cost
 
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Some vehicles just aren't affected. My Volvos lose a lot of power when you put in regular fuels, but they don't knock/ping/or have any other running conditions. Since both of my Volvos are naturally aspirated 5 cylinders, I need all of the power I can get, so they both get premium.
 
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It's just that the engines are calibrated and/or tested to run with what is states in the manual. My manual calls for 87 Octane or higher and I use 87. Have been for the whole life of my Santa Fe and not 1 problem and I beat Government ratings for fuel economy! ;\)
 
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It probably uses a Knock Sensor to pull timing when you fill with 87. Reduce power a little, but other wise should be ok. Putting in a higher octane than required is a waste of money. Octane does not equal power. All octane does is show you resistance to ignition.
 
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per mile cost is lower with 91 gas. lower octane lower power lower mpg. when gas is $3 a gal, make good sense to higher, % gain in mpg exceeds % gain in cost
 

asiancivicmaniac

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Yeah, I'm going to have to calculate the mpg when this tank is done and see if the difference is big enough to use 93.
 
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 Originally Posted By: asiancivicmaniac
My car's owner's manual states that 91 octane fuel is recommended (not required). So I was curious this last time I filled up and put in 87 octane with 2.5 oz of TC-W3. I was expecting a good amount of power loss and knocking, because that's what people on the Maxima board say they experience using regular in a VQ35. But so far I can't feel a noticeable loss of power and I don't think it is any louder. I don't know what knocking sounds like though. So far I have 55 miles on the tank and gas mileage seems to be close to when I use premium, but I won't know for sure until the next fill up. The car has a knock sensor so I guess it's doing its job. Am I just not sensitive enough to these things or is my car working fine on 87?
Its also a longevity of the motor thing.And prematurly wear out sensors quicker.
 
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I have 2000 Maxima. For last 8 years it is fed 87 octane. Sometimes, it has so much power that I don't know what to do with it. Sometimes, it does not. However, I have never been able to correlate it to any factor. My car also has "recommended" 91 octane but it runs fine on 87 without any pinging or knocking. I do dump different types of FI cleaners in the tank somewhat indiscriminately though. - Vikas
 
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When I use 87 in my RX,it develops a different shift pattern,and definitely has less power on the highway.It runs ok,but the winter blended 87 kills any kind of power etc.Mine also (recommends premium)and in this thing,I can definitely tell the difference.
 
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Also, the 87 mixed with the high octane fuel that was in the tank, and you have a net octane higher than 87. It is the first amounts of additives that increase the octane the most - additional amounts are less and less effective. I believe in using the lowest octane that you need, but if they actually recommend 91, I would use it. Power and fuel economy should be better.
 
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My Newly bought 08' Chevy Impala SS recommends 91 octane as well but I see no reason one can use 89 instead. I was also told I can use 87 octane but a much reuced power and fuel economy. If the gas price in my area continues to go up more then most likely I'll begin to use 89 as a standard but for now it'll be 91. Durango
 
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I have found that several of my cars that recomended 91 would run fine or 89. When checking fuel mile over 10 tanks of fuel that the cost was off-set by lower mileage and of course the performance was down if you wanted to get out-of-someones-way fast. I just run what is recomended by the factory engineers.
 
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 Originally Posted By: Eddie
I have found that several of my cars that recomended 91 would run fine or 89. When checking fuel mile over 10 tanks of fuel that the cost was off-set by lower mileage and of course the performance was down if you wanted to get out-of-someones-way fast. I just run what is recomended by the factory engineers.
Thats your best bet!! \:\! Over on Club Lexus we have people saying its a waste of money etc.to use premium.But they are the same people replacing air flow sensors,cleaning iac valves more often,knock sensors and so on,and so on.
 
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I found that by going from 87 to 89 I get one extra Mile per gallon, going to 90 (highest grade in AK) gained maybe extra .25 to .5, compared to 89. When gas hit $3 (it is $3.05 a gallon now up here), mid-grade makes sense financially, assuming 10 cent difference between grades, like it is a norm here. I've been keeping track of mileage for the past 7 years, so it was not a fluke. Car was less to prone to knocking under hard acceleration with 89 than with 87. Winter gas (ethanol blend) cost me a loss of 1.5 MPG, no matter what octane I used. I hate ethanol. That was all on a naturally aspirated V6 in a 2002 Isuzu Axiom. OM recommends 87 or higher.
 
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 Originally Posted By: Ursae_Majoris
I found that by going from 87 to 89 I get one extra Mile per gallon, going to 90 (highest grade in AK) gained maybe extra .25 to .5, compared to 89. When gas hit $3 (it is $3.05 a gallon now up here), mid-grade makes sense financially, assuming 10 cent difference between grades, like it is a norm here. I've been keeping track of mileage for the past 7 years, so it was not a fluke. Car was less to prone to knocking under hard acceleration with 89 than with 87. Winter gas (ethanol blend) cost me a loss of 1.5 MPG, no matter what octane I used. I hate ethanol. That was all on a naturally aspirated V6 in a 2002 Isuzu Axiom. OM recommends 87 or higher.
Every owners manual I ever read always said use 87 octane or higher
 
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