What happens if i dont use Premuim fuel?
#16
I used 87 in my previous 2nd gen. GS3, car ran 166,000 miles without any issues.
i bought the car with 40 some thousand miles.
i bought the car with 40 some thousand miles.
#17
Lexus Champion
iTrader: (1)
As a poor college student there are other ways to save money:
• If you’re a smoker, pick up butts from the street instead of buying fresh packs.
• Reuse coffee grinds at home. You can make a least three extra cups this way.
• Pack a few sandwiches if going out on a date.
• Look for loose change in the sofa.
• Put a half-cup of water in your beer.
• When out with friends say you forgot your wallet and let them pay. Then just forget about it.
• Wash clothes in your bathtub instead of using a Laundromat.
But above all, don’t shortchange your prized Lexus on gas.
• If you’re a smoker, pick up butts from the street instead of buying fresh packs.
• Reuse coffee grinds at home. You can make a least three extra cups this way.
• Pack a few sandwiches if going out on a date.
• Look for loose change in the sofa.
• Put a half-cup of water in your beer.
• When out with friends say you forgot your wallet and let them pay. Then just forget about it.
• Wash clothes in your bathtub instead of using a Laundromat.
But above all, don’t shortchange your prized Lexus on gas.
- Don't smoke
- Don't drink coffee
- Don't get a date/girlfriend
- Don't drink
- Don't go out with friends
- don't wash clothes...
#18
Here is the general rule, without going into all the details:
If your engine was designed for "Regular" or 87 octane, use it. Using higher-grade gas, in most instances, is a waste of money....although premium gas often has more detergent in it to help keep the engine clean. Still, if you use a major name-brand regular, or Chevron or Shell in particular, you shouldn't have problems with deposits and carbon buildup.
If your engine has "Premium RECOMMENDED", you can use regular in a pinch, but not for sustained use. And even if you can use regular, the engine's computer and knock sensor will retard the spark to compansate for the lower octane...so you will be using cheaper fuel but getting less power and poorer gas mileage, and not necessarily saving any money.
If your engine has Premium REQUIRED, there's no choice.....either use premium or risk engine damage and void the warranty.
If your engine was designed for "Regular" or 87 octane, use it. Using higher-grade gas, in most instances, is a waste of money....although premium gas often has more detergent in it to help keep the engine clean. Still, if you use a major name-brand regular, or Chevron or Shell in particular, you shouldn't have problems with deposits and carbon buildup.
If your engine has "Premium RECOMMENDED", you can use regular in a pinch, but not for sustained use. And even if you can use regular, the engine's computer and knock sensor will retard the spark to compansate for the lower octane...so you will be using cheaper fuel but getting less power and poorer gas mileage, and not necessarily saving any money.
If your engine has Premium REQUIRED, there's no choice.....either use premium or risk engine damage and void the warranty.
How does altitude affect these recommendations? What if you live at 5500 feet? Does that extra mile above sea level make a difference?
I mean, up here, they don't even sell anything above 91. Most Phillips 66 Stations here only go to 90 octane.
#19
Lexus Fanatic
It COULD, maybe, affect octane need ay very high altitudes if the mixture is leaned out to the point where the computers and fuel injection can't compensate any more, but you're not likely to spend much time that high.
#20
Here is the general rule, without going into all the details:
If your engine was designed for "Regular" or 87 octane, use it. Using higher-grade gas, in most instances, is a waste of money....although premium gas often has more detergent in it to help keep the engine clean. Still, if you use a major name-brand regular, or Chevron or Shell in particular, you shouldn't have problems with deposits and carbon buildup.
If your engine has "Premium RECOMMENDED", you can use regular in a pinch, but not for sustained use. And even if you can use regular, the engine's computer and knock sensor will retard the spark to compansate for the lower octane...so you will be using cheaper fuel but getting less power and poorer gas mileage, and not necessarily saving any money.
If your engine has Premium REQUIRED, there's no choice.....either use premium or risk engine damage and void the warranty.
If your engine was designed for "Regular" or 87 octane, use it. Using higher-grade gas, in most instances, is a waste of money....although premium gas often has more detergent in it to help keep the engine clean. Still, if you use a major name-brand regular, or Chevron or Shell in particular, you shouldn't have problems with deposits and carbon buildup.
If your engine has "Premium RECOMMENDED", you can use regular in a pinch, but not for sustained use. And even if you can use regular, the engine's computer and knock sensor will retard the spark to compansate for the lower octane...so you will be using cheaper fuel but getting less power and poorer gas mileage, and not necessarily saving any money.
If your engine has Premium REQUIRED, there's no choice.....either use premium or risk engine damage and void the warranty.
Using lower grade fuel on a "Premium Required" engine (usually high compression, highly tuned engines) increases the chance of detonation/knocking.
.
#21
Lexus Champion
the thing is, if you go to 87 and drive like a grandma, you'll never notice a loss in performance. you'll only knock under high load conditions, so if you never floor the throttle and take it to redline, you won't knock, cyl. pressures aren't high enough at low load for knock to even occur.
#23
Lexus Test Driver
Is there anyway you can replace some of your driving with riding a bike?
Also, I don't know if you're a drinker or not, but if you are... cut back on it. By far one of the most expensive things for college students.
Also, I don't know if you're a drinker or not, but if you are... cut back on it. By far one of the most expensive things for college students.
#25
Tech Info Resource
iTrader: (2)
As far as I know, altitude doesn't affect the need for octane. Without a turbo or supercharger, it leans out the air-fuel mixture, but modern engine computers and fuel injection compensate for that.
It COULD, maybe, affect octane need ay very high altitudes if the mixture is leaned out to the point where the computers and fuel injection can't compensate any more, but you're not likely to spend much time that high.
It COULD, maybe, affect octane need ay very high altitudes if the mixture is leaned out to the point where the computers and fuel injection can't compensate any more, but you're not likely to spend much time that high.
It's PHYSICS. Less air in the cylinder from reduced intake pressure means less heat generated by compression which means LESS propensity for compression ignition issues.
And NO even with carburetors, jetting compensates for altitude up to 10k feet. I've lived in Colorado and tuned engines to run at altitude. Pilots jets are actually BIGGER and main jets are smaller at altitude.
Last edited by lobuxracer; 06-17-08 at 11:24 AM.
#26
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Seems to me the rule of thumb was in the range of 1-2 reduction in octane requirement per 1,000 feet of altitude. But that is biggest in engines that few here have familiarity with other than those flying gen av or gettting '50 Pontiacs. I have seen numbers that modern engine management systems that are monitoring many of the variables that are affected by altitude, like manifold air pressure and mass air flow have reduced that number to less than .5 drop in octane requirement per 1,000 feet.
#27
Lexus Fanatic
Are you serious? NO! Altitude DIRECTLY affects octane requirements. The higher you are, the less octane you need - that's why mountain states like Colorado don't have and don't need 93 octane premium. 91 works just as well.
It's PHYSICS. Less air in the cylinder from reduced intake pressure means less heat generated by compression which means LESS propensity for compression ignition issues.
And NO even with carburetors, jetting compensates for altitude up to 10k feet. I've lived in Colorado and tuned engines to run at altitude. Pilots jets are actually BIGGER and main jets are smaller at altitude.
It's PHYSICS. Less air in the cylinder from reduced intake pressure means less heat generated by compression which means LESS propensity for compression ignition issues.
And NO even with carburetors, jetting compensates for altitude up to 10k feet. I've lived in Colorado and tuned engines to run at altitude. Pilots jets are actually BIGGER and main jets are smaller at altitude.
Yet one matter still stands. The higher you go, the thinner the air gets. That causes an over-rich mixture, which lessens the need for high octane if you don't lean it out, as computers now do. Lean it out too much, though, and you get pinging and detonation, which incrases the need for octane right back again.
I also have some experience with engines and altitude. I am an ex-pilot and Instructor, with a rating in light (under 12,000 lb) piston-engine aircraft. I had to know...and teach..... how to identify aviation gas (avgas) by dye color, octane, check the fuel ***** for water and dirt, how to properly lean and enrich with manual carburator and mixture controls, govern propeller RPM, and co-ordinate this with throttle action....it is not always easy. But an light-aircraft piston engine is very similiar to a flat-4 or 6 car engine, except for air cooling. And many light aircraft, particularly older ones, don't have computers or fuel injection....you had to manage the engine(s) yourself.
#28
do 2nd generation GS's "REQUIRE" or "RECOMMEND" premium??
to be honest i've been using 87 for a while now.. 60 mile daily driver has forced me to switch
to be honest i've been using 87 for a while now.. 60 mile daily driver has forced me to switch
#30
Lexus Fanatic
I can't totally answer your question (second-gen GS models, of course, have a number of different hybrid and non-hybrid powertrains, V6's, and V8's), but you might be able to get an ECU reprogramming of the engine's computer to allow regular use (no pun intended ) of regular 87 octane. Ask the service people at your local Lexus shop. Factory-approved ECU reprogramming is available for some makes and models.....not sure about your GS.