using regular gas

been using reg in mny05 rx 330 since day 1, no issues, 60k+ miles __________________________________________ Never argue with an idiot. They'll drag you down to their level and beat you with experience.

I think the knock sensors will prevent any damage. Been using regular in my '01 RX300 for 158k miles and it's still running fine (knock on wood). Bob

Ray O has pointed out in the past that while there may be no noticeable difference in performance, it's a good idea to check out the gas mileage for a couple of tankfuls. It's possible that any savings in price per gallon may be offset by a small decrease in your average mpg when using regular gas.

Thank you all.

Jeff

It is nice to know somebody pays attention to my posts!

There's more than one of us who pays attention. Thanks for all the information you post. Bob

You are always very welcome!

This newsgroup would be nearly worthless without you. There are lots of people who are self-proclaimed experts on usenet, and only a handful who really know what they're talking about and go out of their way to inform people. Offering to dismantle your own visor to help a total stranger was way beyond the call of duty!

Thanks for all the info you post here.

Well, I didn't take it completely apart, just far enough to figure out what was holding it together ;-)

Yes, Ray O, your excellent contributions are deeply appreciated. I think the real answer to this depends on the difference between regular and premium gas. Here regular is about 380 today and premium runs about 405. So if I get 15 mpg around town, then if I switch to regular, I need to get more than 380X15/405 or about 14.1 mpg to save anything by going to the lower grade. My problem is that I find variations bigger than this in my milage from one tankfull to the next. So I stick with the high priced stuff.

I wish premium was only $4.05 where I am! Regular is $4.30, with mid-grade

20 cents more and premium another 10 cents above mid-grade.

I've tried 4 or 5 tanks of mid-grade, I'll have to calculate cost per mile again and see if there is any savings from premium.

I've been getting between 17.6 and 18.1 MPG around town in my 2001 LS 430, I was getting between 18.6 and 18.9 with premium so there is a slight MPG penalty with mid-grade. My mileage is pretty consistent except when I take a highway trip of 30 minutes or more during the tank, when my tank MPG goes to about 20.1. On long trips where the entire tank is highway, I get about

25 MPG if I don't use the cruise control, and around 24 MPG if I use the CC. If my wife or kids drive the car, fuel economy goes down by at least 1 MPG.

I suppose if I slowed down and wasn't passing people around town all the time and kept my highway speed below 80, I could probably get a little better fuel economy, but old habits die hard.

Just would like to add that a trip computer alone can save you 10% in gas by making you drive more sensibly.... my '06GS300 AWD also indicates mpg on the display located inside the speedometer. Unfortunately, this Lexus gadget reads constantly high by 1.5 mpg, whereas my '05 Avalon's mpg reading is right on the money. On another note, I had a pleasant surprise, I switched to regular around 20K miles based on a Lexus rep's recommendation, but my mileage did not go down overall, true the city mpg is slightly lower, but the highway mpg is just as high if not higher. On a recent trip (July Fourth weekend) through PA and NJ, I saw my mpg reading reach 34 mpg (meaning 32.5 actual). When I finally bought gas, it confirmed, I had done the trip from Deep Creek Lake MD to Fishkill NY, 422 miles on about 13.1 gallons. I was driving with the traffic, mostly over the speed limit by 5-10 mph. This is just for the record. Last year, using some Hi test and lots of Reg gas, I averaged 27.1 mpg actual, with mostly highway driving and very little city driving. I have the data to back all this up and I do not drive like a slow poke, as a matter of fact my Lexus likes to be around 60-65 mph, does a car have a personality!!!!!!!!!!!!!!!!!

/Kitzler

Self service premium where I am (East Hampton, NY) is $5.14 this week.

My '04 GS430 is consistently 18 city/21 hwy with premium, which is, surprisingly, just about the same as my '02 GS300 was.

I've been entertained by this "regular gas" thread recently, and I have two small comments.

1). This is the first time I've ever seen my suspicions corroborated, that say I can get better fuel mileage without a cruise control, that with one. (Noted from the previous comment(s)). 2). My other suspicion is that the performance of these vehicles using regular/premium etc. is a lot more related to *actual* gas in the ground, rather than the vehicles reaction. IOW, the real octane in the ground, as well as, the age of the fuel, temperature, holding tank age/condition, dispensing equipment condition, etc., etc.

Additionally, I was recently told by a local gas company representative that a 6.5 ounce variance on a 10 gallon volume, was allowed to remain in compliance to local weights and measures.

That seemed quite high to me, but if correct, will certainly affect mpg calculations. Especially, if one frequents different stations.

I think that the cruise control tries to make too many throttle adjustments to maintain speed, instead of letting speed creep down a little on uphill stretches and build up on downhill stretches.

I have no information with which to back up or refute that suspicion, but I tend to agree.

Sounds reasonable. Let's see...128 ounces in a gallon, so 1,280 ounces in 10 gallons...

Dividing 6.5 by 1280 gives 0.51% (approximately). Half a percent relates to about $0.02 per $4.00 gallon, which seems like a fair amount of tolerance, given the relative crudity of the dispensing system (accuracy of the meter, gas remaining or not remaining in the hose, etc.) Actually, on thinking about it, I'd be pretty happy if the pumps at the local station are actually that close.

Yeah, at $.02, it doesn't sound like much. A lot less than the 6.5oz/1,280oz ratio. At least to me.

But, consider:

Fuel dispenser volume shorted on a 10 gallon fill: (200 mile trip / ((1,280oz - 6.5oz) / 128oz)) = 20.102080mpg

Fuel dispenser volume equal on a 10 gallon fill: (200 mile trip / ((1,280oz - 0oz) / 128oz)) = 20.000000mpg

Fuel dispenser volume longed on a 10 gallon fill: (200 mile trip / ((1,280oz + 6.5oz) / 128oz)) = 19.898950mpg

Of course, your manual calculation would always net to 20mpg. But, behind the curtain, the values are quite(relatively speaking) different.

Get real! 6.5 oz in 10 gal is about 1/2 of one percent. The error here is absolutely trivial, and of no consequence to your calculations.