92lexus300 Posted March 23, 2005 Share Posted March 23, 2005 I recently I bought a Lexus ES300. It is a 1992 and I would like to know if it requires PREMIUM fuel? I just put regular fuel as I am assuming it is the same engine as the Camry, is it not? Your post will be appreciated. Quote Link to comment Share on other sites More sharing options...
SKperformance Posted March 23, 2005 Share Posted March 23, 2005 if you don't want to replace egr's o2 and other sensor it does Quote Link to comment Share on other sites More sharing options...
G and C Johnstone Posted March 23, 2005 Share Posted March 23, 2005 I would like to try to help with this question. If you have access to the owners manual for your car it will suggest the optimum fuel octane. Believe it. Your Lexus car is very smart and it can detune itself to run well on low test fuel but it will loose performance and efficiency and as SK has suggested durability may go out the window as well. By way of an explanation, consider this; Your engine burns a mixture of petrol and air in its combustion chambers to do its work. Size it up a bit and consider the cylinder at the size of your lounge room. The Lexus is a performance engine so it is quite high compression so the far wall of the lounge moves to within a couple of feet of the end wall before the spark plug fires the mixture to blast the wall back down the cylinder to give masses of power. In a lower performance low compression engine the wall would not get nearly so close to the end of the lounge before it reached the end of travel and the spark plug fired the petrol to power the wall away. A low performance engine still makes plenty of power and has the advantage of using more energy dense fuel but it does not have that extra compression to kick off every power stroke with such an urge. This is the sparkle that is available at all throttle openings in a high compression engine. (A diesel engine is a different matter and could confuse my arguments) If low octane fuel is used in Lexus engines the spark plugs have to ignite the fuel much later in the engine cycle to prevent detonation. Detonation is when the burning fuel increases the pressure in the cylinders and a second flame front spontaneously occurs further increasing pressure until an explosion occurs. High octane fuel burns more slowly and resists compression ignition and knocking. Using fuel of a higher octane than spec will not result in any gain and should result in more petrol being used. As a young fool I used to play with small bike engines and to make them run on alcohol mixtures we used to attack the carburetor jets with drills to make them bigger to get enough fuel to run cleanly. Lower than optimum octane must lower efficiency and smoothness. Any miss fire at all is bad for the parts after the combustion process. These parts are not expecting unburned fuel in any great quantity. When I was little I used to believe that the fuel companies used super petrol to wash out the diesel and kerosene tanks before putting other products in them and then the rinse fuel was called regular. As an old cynical person I still believe that the higher cost is a protection against what could be less than best. Graeme Quote Link to comment Share on other sites More sharing options...
exdotcomer Posted March 23, 2005 Share Posted March 23, 2005 I would like to try to help with this question. If you have access to the owners manual for your car it will suggest the optimum fuel octane. Believe it. Your Lexus car is very smart and it can detune itself to run well on low test fuel but it will loose performance and efficiency and as SK has suggested durability may go out the window as well. By way of an explanation, consider this; Your engine burns a mixture of petrol and air in its combustion chambers to do its work. Size it up a bit and consider the cylinder at the size of your lounge room. The Lexus is a performance engine so it is quite high compression so the far wall of the lounge moves to within a couple of feet of the end wall before the spark plug fires the mixture to blast the wall back down the cylinder to give masses of power. In a lower performance low compression engine the wall would not get nearly so close to the end of the lounge before it reached the end of travel and the spark plug fired the petrol to power the wall away. A low performance engine still makes plenty of power and has the advantage of using more energy dense fuel but it does not have that extra compression to kick off every power stroke with such an urge. This is the sparkle that is available at all throttle openings in a high compression engine. (A diesel engine is a different matter and could confuse my arguments) If low octane fuel is used in Lexus engines the spark plugs have to ignite the fuel much later in the engine cycle to prevent detonation. Detonation is when the burning fuel increases the pressure in the cylinders and a second flame front spontaneously occurs further increasing pressure until an explosion occurs. High octane fuel burns more slowly and resists compression ignition and knocking. Using fuel of a higher octane than spec will not result in any gain and should result in more petrol being used. As a young fool I used to play with small bike engines and to make them run on alcohol mixtures we used to attack the carburetor jets with drills to make them bigger to get enough fuel to run cleanly. Lower than optimum octane must lower efficiency and smoothness. Any miss fire at all is bad for the parts after the combustion process. These parts are not expecting unburned fuel in any great quantity. When I was little I used to believe that the fuel companies used super petrol to wash out the diesel and kerosene tanks before putting other products in them and then the rinse fuel was called regular. As an old cynical person I still believe that the higher cost is a protection against what could be less than best. Graeme ← nice Graeme, i couldn't have explained it better myself. No really, i couldn't. (too lazy to type all that) Basically, would you agree- you get what you pay for? Quote Link to comment Share on other sites More sharing options...
meeters Posted March 23, 2005 Share Posted March 23, 2005 I would like to try to help with this question. If you have access to the owners manual for your car it will suggest the optimum fuel octane. Believe it. ..... Nice write up, Graeme. My manual recomends 87 octane rating fuel or higher. I've always used 91 octane or better around town since it SEEMS to give better performance in stop and go driving. If I'm on a long trip with a lot of highway driving I switch to 87 octane, the higher octane doesn't SEEM to make a difference during this type of driving. With the price of 91 octane at $2.45/gal during the last week here in W. Mich, I've been running 87 octane around town too. We'll probably see $3 bucks a gallon around here for the good stuff this summer. Quote Link to comment Share on other sites More sharing options...
92lexus300 Posted March 23, 2005 Author Share Posted March 23, 2005 Thanks for the tip Graeme .. one thing I am not sure about is the engine for the 92 ES300 ... is it not the same as the Camry V6 for that year? Quote Link to comment Share on other sites More sharing options...
SKperformance Posted March 24, 2005 Share Posted March 24, 2005 read the faq I spent a few weeks making it to help new members with basic questions. Please be considerate for the time i put into making it by finding it your self rather than making me retype it again and again and again. Quote Link to comment Share on other sites More sharing options...
92lexus300 Posted March 24, 2005 Author Share Posted March 24, 2005 Well SKperformance, the reason I asked that question is because I did search for the engine specs and it turns out to be the same between camry and lexus es300 .. That brings me to the question, howcome the lexus es300 requires premium fuel? Quote Link to comment Share on other sites More sharing options...
monarch Posted March 24, 2005 Share Posted March 24, 2005 The Lexus FAQ at Lexus.com explains why the V8's need premium: Fuel Recommendations Question Is premium fuel required? Corporate Lexus Answer: "The engine and engine management system of Lexus vehicles with V8s were specifically designed to deliver high performance. One aspect of high performance design that affects fuel requirements is a high compression ratio. Use of premium fuel will take full advantage of the high compression ratio of the engine of your vehicle. Use of lower grade fuel will typically cause some degree of improper combustion, which results in engine knock. When the engine management system detects knock, such as with the use of lower grade fuel, the ignition timing will be retarded. While retarding ignition timing helps to minimize knock, it also reduces available performance and fuel economy." The early 90's V6's may have lower compression ratios in which case they'd be more tolerant of regular fuel. I agree with SK Performance, however, that if you use premium, the life of some components like the oxygen sensors / cat converters / fuel injectors etc. will be extended which helps offset the cost of premium. Quote Link to comment Share on other sites More sharing options...
vcv10guy Posted March 30, 2005 Share Posted March 30, 2005 Well SKperformance, the reason I asked that question is because I did search for the engine specs and it turns out to be the same between camry and lexus es300 .. That brings me to the question, howcome the lexus es300 requires premium fuel? ← The engines are exactly the same, and in my 1992 Toyota Camry owner's manual it recommends 91 octane as well for the 3VZ-FE V6 engine. Basically you should be using premium (91 octane) in both your ES300 and Camry V6. I have both vehicles (see my sig at the bottom) and I use premium when I use either one of them. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.