My 91 Camry is down and out for now from engine gunk, and I'm wondering if I should have been putting premium grade in it instead of regular.

My sister had an 1986 Chevy Nova/ Toyota Corolla that would break down in traffic if bad gas was put in it, but was otherwise very reliable. I have heard some mechanics say grade is everything, or also that it means nothing.

Do you think there is any difference in the grades?

No idea. You might try to Goggle up some gasoline or gas vehicle groups:

• http://townhall-talk.edmunds.com/direct/view/.f0e7ce5
• http://www.topix.com/forum/autos/toyota-camry
• http://forums.cnet.com/5204-7811_102...mID=78&start=0

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

Hi Angry Aspie,

We have fueled our "92 Camry Wagon, 6 cylinder engine with alternate
fill-ups of Mobil's Special and Premium grades of gasoline since we got it
new in 1992. The manual called for an octane value that matched the
average of these two grades. It's performed flawlessly and expect to hit
100,000 miles on this tankful.

Good luck with your Camry, it deserves the best (proper octane)!

Galileo

Driving the Honda Civic Hybrid: "Priceless"

Galileo

It's not so much the grade/octane rating of the gas as the quality of the gas. Buying cheap gas now means you'll pay for it later with a gunky engine. Spending the extra buck or two on each tank on quality gas (I use BP or Shell) will keep your engine cleaner and save on maintenance in the long run. A 5 cent difference between brands for the same grade seems like a lot until you realize that on 20 gallons, the difference is only $1.

The octane rating has to do with how stable the gas is under compression, which means little in an Atkinson cycle engine. That's why you can buy 108 octane racing fuel, which has a higher ethanol content.

Back when I bought my Blazer, I had nothing but problems after about 6 months. I was using cheap (Jewel and Meijer) gas and my brother was using cheap gas when he had it. I got the engine tuned up and cleaned out, and even cleaned a bunch of sludge out of the tank when I replaced the fuel pump. A year later when I had to replace the fuel pump again (long story short, don't buy the cheapest pump even if it has a lifetime warranty) and the tank was spotless. After 2 years of using quality gas, the engine was running perfectly when I sold it, and getting slightly better gas mileage than when I bought it.

I agree that quality is the key to preventing most fuel problems. Of course, one should always use the octane fuel specified by the owner. Going to a higher octane rating wastes money and provides no benefit. With the altitude here regular is rated at 85 octane but my HAH is speced for 87, so I am usually stuck with buying mid-grade.

Because most areas are like where I live here in Casper in that all the gas comes from the same refinery, (Sinclair is this case), differences in quality of fuel are related to the local station storage. Any additives unique to a brand, EXXON, Shell etc., are added just prior to a delivery. The basic fuel is the same. Some stations here, notably CONOCO, sell a 10% ethanol blend. I am not sure where that comes from but I would bet it is also a custom blend using the local product. I don't purchase ethanol in as it is usually the same price but has less energy content and I can notice a drop in MPG.

Since one can't examine the insides of the storage tank at the station, one option is to buy gas at stations that do the most volume of sales. The turnover in the storage tanks is probably high and therefore the potential for accumulation of sludge is low. I my case the usual fill is done at an EXXON station because it is always the lowest price or a tie for low, has non-ethanol fuel, and seems to do a large volume of business.

R. Mark Owens - Casper Desert Mist

Our regular grade is 85 octane here in the Denver area as well. The higher altitude areas offer the lower octane regular because the octane requirement for a given car drops with increases in altitude. I've asked the service guys at my local Honda dealerships and they've told me that 85 is fine for our altitude. However, I've seen information that today's newer cars experience less of an altitude effect.

Personally, I've been using 85 octane in my 2006 Honda Civic Hybrid except for maybe one tank. I've noticed no ill effects.

Hmm, I was called stupid in other thread so take or leave my opinion as you want.

In older cars (with no computers) it was pretty important to use the correct grade because the advance(timing) of your valves was set up for the particular grade. Smaller (more precise) engines were particularly sensitive and usually required higher grades.

In modern cars, there is usually a variable timing (computer takes care of it) so it has became less important.
But I would always recommend to sort of follow what is required (or recommended) by the manufacturer. Or have the real professional to tune up yor engine.

And if you worry about your engine, do not put there ethanol (or gas with high volume of ethanol). It can mess up your small engine pretty well. (and gas with ethanol is always less pewerfull so the MPG is worse)

Rgds
John

It seems that older foreign cars (which mine is) are more sensitive to fuel brand and octane. My car also has a carburetor, which makes it even more sensitive.

As for brand, I always buy Shell, BP, or Chevron. The octane where I live runs from 87-93.

I think once I get new fuel and air filters on it Wed. that it will be ok

I may be dreaming but I think that my owners manual for the HAH specifically says not to use lower octane at higher altitudes.

R. Mark Owens - Casper Desert Mist

I have no facts to back this up, but from my anecdotal evidence, I've found that quality is the most important too.
Before I bought my FEH, I had a '98 Mustang GT (big switch, I know). It was a stick, and every time I put "cheap gas" in it, it would not idle without me pressing on the accelerator. I'd push in the clutch in or put it in neutral, and it would die.
I noticed that it only happened a couple of days after I went to a Speedway Gas Station (I don't think those are everywhere, but they are cheap). And it would start acting normal after I ran it for a while. So, after I figured it out, I never went back, and would never consider putting it in my FEH.
It could have been a ethanol content thing instead of quality, but I'll never go back. I only go to Marathon, Shell, or BP now.