Just a question. We had the hurricane in Louisiana. And all I can find is reg grade gas. No premium. Is using reg grade gonna have any effects on my car? I have a half tank left and gonna try to hold out till I can find proper gas but might not have that option. Any input would be grateful.

 

No serious issues over the long term but you will experience less power under higher RPM's. Lower RPM's won't affect much if anything (the ECU compensates for the knocking that it senses and adjusts the timing to prevent knocks.)

 

Alright thanks.

 

Less power, less responsive acceleration, lower gas mileage, higher/faster carbon buildup, etc. are all possible

 

We have a high compression ratio engine in our IS model, that's why manufactory require premium gas. The regular gas has lower octane than premium, meaning the gas is burning faster than premium gas. So, think about what will happen when the gas burnt out before hitting the spark plug? The extremely high pressure going up to the spark plug from the piston and the high pressure going down to piston. It will cause the engine blasting over and over and you will hear some clok clok sounds. That's definitely no good for the engine. So I suggest you to find a proper gas station to add up premium gas.

 

would it help if he bought octane booster

 

As a couple others posted... the ECU will compensate for the lower grade fuel. It has a knock sensor to avoid detonation (which is what Jason is describing). When the ECU makes that compensation (retarding the timing), you lose power, acceleration, and throttle response. This is old technology. My 1992 turbo MR2 has a knock sensor to avoid detonation.

The regular gas also has more contaminants, which will speed up the carbon build up issue that comes along with direct injection vehicles. Direct injection is becoming more main stream, which is why you see a lot of major fuel companies adding detergents to their premium lines.

A fill up with regular will not hurt if you are pressed for gas, I just wouldnt make a habit of it.

 

Not really.

When a can of octane booster says it adds 8 "points" of octane it means it turns 87 into 87.8. Waste of money.



For a tank or two regular will be fine, just go easy on the car, and back to the proper fuel soon as you're able to.

 

Octane booster is a complete scam......

 

Thanks everyone for the info. All stations say they don't know when they will have prem. again. Lexus should be nice and fill me up.

 

They should hook you up with at least a little bit but I know they are going to also tell you that regular is fine for short term use, I could swear I read on something official from Lexus (maybe the manual?) that if premium is not available regular will suffice for a short term meaning until the next gas station like if your on a road trip. Octane booster is a rip off but hey .8 helps a little bit for peace of mind if your that worried about it. If you have half a tank of premium add mid grade and a thing of octane booster that would put you pretty close to 91 which is all you need.

 

I even heard alcohol can increase the octane. Some gas station also use them, but it's rare. Just saying not try to recommend, nor using a octane booster.

 

Hey if there's no premium around and you need to use your car, you got no choice! lol you aren't going to serious engine damage driving it 1 or 2 tanks on regular fuel, you should be fine. It's just gonna feel sluggish and you might hear the knocking. Just fill her up with premium as soon as you can again

 

Any ideas on how much lower the gas mileage may be between premium and regular?

 

Depends on the type and style of driving... generally low enough it's not worth using if you have a choice though.