Well, I fell for it. There has been a lot of discussion about being OK to use regular gas even when the manufacturer recommends premium. I have read many times that the ECU will compensate for the lower octane and adjust the timing accordingly. So yesterday I convinced myself to give it a try. Since I had half a tank of premium, I'd only be adding half a tank of regular, so I was sure my '04 LS430 wouldn't be able to tell the difference. Smart car....stupid me. I now hear pinging even with mild 5th gear acceleration on flat, level roads. Could it be because the temperature is in the 90's, the humidity high? Can't tell the difference in performance or gas mileage, but I sure hate to hear my baby in pain.

Just thought I'd warn anyone thinking about trying regular grade gasoline to evaluate the savings vs. the feedback you will get from your engine. I figured that half a tank of regular saved me a whopping $2.00 over premium. Sure seems like false economy to me now.

It could have been worse. It's better to learn than to not learn at all. But hey, with the $2.00 you saved you can buy Kung Fu slippers or even 8+ packs of Top Ramen noodles.

Well, I fell for it. There has been a lot of discussion about being OK to use regular gas even when the manufacturer recommends premium. I have read many times that the ECU will compensate for the lower octane and adjust the timing accordingly. So yesterday I convinced myself to give it a try. Since I had half a tank of premium, I'd only be adding half a tank of regular, so I was sure my '04 LS430 wouldn't be able to tell the difference. Smart car....stupid me. I now hear pinging even with mild 5th gear acceleration on flat, level roads. Could it be because the temperature is in the 90's, the humidity high? Can't tell the difference in performance or gas mileage, but I sure hate to hear my baby in pain.

Just thought I'd warn anyone thinking about trying regular grade gasoline to evaluate the savings vs. the feedback you will get from your engine. I figured that half a tank of regular saved me a whopping $2.00 over premium. Sure seems like false economy to me now.


I agree........in part. I tried a full tank in my 92 sc400. While I experienced no pinging, the performance drop was substantial. Mind, it was 2 weeks ago when we here in the NorthEast were slammed with super high humidity and high heat. This I'm sure contributed to the issue. I also noticed my mileage was slightly decreased. I credit this to me being heavier on the foot due to the decrease in performance. She now has a fresh tank of 93 Octane! I think the car was so happy, it goosed me while driving!! :D

What's worse is when someone borrows your car and puts $10 worth of 87 octane as if they are doing you some kind of favor. My Strange Rover drove funny enough as it did the last thing you want is when your doing 70 on a highway and you feel this strange pull when changing gears.

yeah that's right, it could have been worse, the ecu is trying to retard the timing as much as it can already

come on, you got an ls430, pay for the gas :) (just kidding)

Note to self: don't buy an LS from MikeP. :cylon:

OK you guys. I feel bad enough already. I swear I saw tears dripping from my car's headlights and I don't have washers. It's like I cheated on her :cry: . I had to promise that I would fill her with 93 octane as soon as her tank is almost empty....and that I would massage her with a coat of NXT.

I dunno if the LS has an anti-syphon feature, but i'd try to syphon out all the gas and replace it with premium!

add a bottle of octane booster NOW. any brand. I recommend NOS

http://www.speeding.co.uk/acatalog/12010.jpg

i agree... just add some octane booster...

i agree... just add some octane booster...
they dont work, do they? at least i dont think they do. :(

they dont work, do they? at least i dont think they do. :(
Some of them do.

add a bottle of octane booster NOW. any brand. I recommend NOS

http://www.speeding.co.uk/acatalog/12010.jpg
the only octane booster I would use is a gallon of xylene or toulene from the paint store.

MikeP - I'm sure you're a smart guy, and since you drive an LS430 I assume you're not broke, but trying to save $2 a tank on a $60,000 car when I think your manual explicitly states that you should put at least 91 octane in the car makes no sense.

It's amazing to me how hyped up people get about gas prices. I can understand it if someone's a checkout clerk at Wal*Mart, but for probably just about everyone on ClubLexus it's just not that big a deal.

OK you guys. I feel bad enough already. I swear I saw tears dripping from my car's headlights and I don't have washers. It's like I cheated on her :cry: . I had to promise that I would fill her with 93 octane as soon as her tank is almost empty....and that I would massage her with a coat of NXT.

well, we had to get hard on you so you don't do it again :) but in any case, i think you should detail the car in and out now just to make her happy!

MikeP - I'm sure you're a smart guy, and since you drive an LS430 I assume you're not broke, but trying to save $2 a tank on a $60,000 car when I think your manual explicitly states that you should put at least 91 octane in the car makes no sense.

It's amazing to me how hyped up people get about gas prices. I can understand it if someone's a checkout clerk at Wal*Mart, but for probably just about everyone on ClubLexus it's just not that big a deal.

Don't be so sure that I'm a "smart guy". :confused: My thought process was this: I have half a tank of 93 octane....I will add half a tank of 89 octane. In my simplistic mind, that would average 91 octane, which (I think) is acceptable to Lexus. Maybe the molecular composition of gasoline doesn't adhere to simple math or maybe my car's brain takes as long as mine does to adjust to change :uh: Anyway, it was a bad idea and I have already written "I will never use 89 octane gas again" 200 times.

MikeP - I'm sure you're a smart guy, and since you drive an LS430 I assume you're not broke, but trying to save $2 a tank on a $60,000 car when I think your manual explicitly states that you should put at least 91 octane in the car makes no sense.

It's amazing to me how hyped up people get about gas prices. I can understand it if someone's a checkout clerk at Wal*Mart, but for probably just about everyone on ClubLexus it's just not that big a deal.


The gas prices arent going to hurt the wallet too much, I mean it cost $40 to fill up instead of 30, but it just sucks paying higher prices. I dont know how other feel but when it costs $2.52 to fill up one week and then $2.88 the next, Im thinking WTF happened to the prices? Does it need to go up that dramatically?