Am I Imagining Things

[Rolm]

Am I Imagining things

I decided to fill-up my 99 3.8 Intrigue with premium fuel and the engine seems to be much stronger. I believe I can feel a real difference. What do you think am I imagining things and wasting my money on filling-up with premium fuel.

[maxwedge]

Waste of money, relatively low compression engine designed for 87 0ctane, in stock form

[jdl]

My info says if the owner's manual says to use regular, then your wasting your money buying premium.

If your vehicle knocked or pinged using regular, switching to premium should help. If the knock sensor detected a knock, it should retard the timing a little, if it is retarded too much, you would notice a performance issue. I can't say that the difference you feel is a timing issue, I don't know.

There is a higher detergent gasoline, called " top tier gasoline ", they say it will help performance, supposed to clean injector and intake valve deposits, better than the other gasolines. Gasoline is so high around here, I get the cheapest stuff I can find.

[samova2133]

I have also noticed that premium fuel seems to run smoother. I do not think it is our imagination. I think it is related to the flame front being more controlled and less explosive and expanding more evenly with the premium fuel.

[LittleHoov]

The only way to tell for sure would be to hook it up to a scantool and test it under similar circumstances with each grade of gasoline to see what sort of timing you were getting.

I switch between 87 and 89 quite often, because several stations around here offer 89 at the same price if not cheaper than 87 because its 10% ethanol, and that little bump in octane seems to make no difference to me.

[Jimmy Olsen]

There was previously a thread that discussed this issue. I know that the Northstar engine senses if knocking occurs and retards the timing automatically. Different years of the Intrigue recommend either regular or mid-grade. The best reason to buy premium gas is to get extra additives that prevent carbon build-up. For tier-one gas, premium usually has 5 times the additives that regular has.

People who buy no-name gas from Mom and Pop stores to save a few pennies short-change themselves because usually the gas doesn't have very much (if any) additives in it.

['97ventureowner]

Originally Posted by Jimmy Olsen

People who buy no-name gas from Mom and Pop stores to save a few pennies short-change themselves because usually the gas doesn't have very much (if any) additives in it.

Not necessarily. Around here the smaller, independent gas stations purchase their fuel from an intermediate supplier,and it comes from"The Big Guys"(Mobil, Sunoco, Citgo), and it's the same gas as you'd get at the corporate branded stations.It's like buying a store brand product made from a national brand manufacturer, it just has a different label.

[Rolm]

The reason i am buying premium these days is due to the fact that premium costs only 6 cents more per litre vs regular gas. Here in the Toronto area the Esso staion sells regular for $102.9, Mid-Range and Premium for the same price of $108.9, I asked the attendent why the mid range and premium are the same price he said they have an over supply of premium due to more people using regular in their cars. As long as premium is sold at that small price difference vs regular I will use premium the 3.8 is running better.

[Jimmy Olsen]

Originally Posted by '97ventureowner

Not necessarily. Around here the smaller, independent gas stations purchase their fuel from an intermediate supplier,and it comes from"The Big Guys"(Mobil, Sunoco, Citgo), and it's the same gas as you'd get at the corporate branded stations.It's like buying a store brand product made from a national brand manufacturer, it just has a different label.

I agree that all the gasoline comes from the same refinery. However, prior to the tanker getting their load of gasoline, the driver adds the additive package. If you don't buy a tier-one gasoline you don't know what you are getting in terms of the additives. Out of the tier-one gasolines I would say that Chevron additives (Techron) are best followed by Shell V-power.

A study of independent gasoline stations shows that they sometimes don't even meet the federal standards for additives to prevent clogging of fuel injectors.

So, the bottom line is that it is worth spending a few pennies more for tier-one gasoline.

[Jimmy Olsen]

Originally Posted by Rolm

The reason i am buying premium these days is due to the fact that premium costs only 6 cents more per litre vs regular gas. Here in the Toronto area the Esso staion sells regular for $102.9, Mid-Range and Premium for the same price of $108.9, I asked the attendent why the mid range and premium are the same price he said they have an over supply of premium due to more people using regular in their cars. As long as premium is sold at that small price difference vs regular I will use premium the 3.8 is running better.

The primary reason premium has a higher octane rating is because the hydrocarbons in it have a longer chain than those in regular or mid-grade. The longer chain molecules burn cleaner and leave much fewer deposits on the valves and cylinders. Here in Oklahoma premium costs 20 cents more a gallon than regular.

Probably the reason the 3.8 is running better is because the gas has plenty of additives and its burns cleaner. Hence, the engine has more pep.

[Rolm]

Originally Posted by Jimmy Olsen

I agree that all the gasoline comes from the same refinery. However, prior to the tanker getting their load of gasoline, the driver adds the additive package. If you don't buy a tier-one gasoline you don't know what you are getting in terms of the additives. Out of the tier-one gasolines I would say that Chevron additives (Techron) are best followed by Shell V-power.

A study of independent gasoline stations shows that they sometimes don't even meet the federal standards for additives to prevent clogging of fuel injectors.

So, the bottom line is that it is worth spending a few pennies more for tier-one gasoline.

Great points you have made and they make sense. The last time I filled-up at a no name gas station was around 35 years ago. I filled up at a canadian tire gas station. After filling-up in exiting the gas station I had to make a left turn I nailed the gas pedal to avoid been hit by uncomming traffic it felt like I had my emergency brake on and I checked and it was "not" on that is how poorly my car ran after filling-up with a no name gas and I also got the worst milage. That was the last time I filled up with no name. Oh yes my car at the time was a 67 Cougar with a 289 auto. One other point I find that my 99 Intrigue doesn't seem to run as well on Sunoco regular gas. I find that it runs best with Esso

[phewop118]

Yours doesn't run well on sunoco regular? I seem to have good gas mileage and normal performance with that. That being said, I always use BP/Amoco, as there are many of them conveniently located on my routes. Whenever I can, I use shell. Never will I use Getgo or Kwikfill or Sheetz. Back when gas dipped down to the low 2's, I started using premium for a little while and didn't really notice a difference. Just curious, someone mentioned that some intrigues require 89 octane. I thought they all only called for regular, no matter which engine. Can someone back my thought up?

[Jimmy Olsen]

Originally Posted by phewop118

Yours doesn't run well on sunoco regular? I seem to have good gas mileage and normal performance with that. That being said, I always use BP/Amoco, as there are many of them conveniently located on my routes. Whenever I can, I use shell. Never will I use Getgo or Kwikfill or Sheetz. Back when gas dipped down to the low 2's, I started using premium for a little while and didn't really notice a difference. Just curious, someone mentioned that some intrigues require 89 octane. I thought they all only called for regular, no matter which engine. Can someone back my thought up?

Mu understanding is that the '99 owners' manual recommends 87 octane, and the '00 manual recommends 89 octane. The GM Helms service manual recommends premium.

[dtownfb]

Rolm: I have no doubts that your engine did feel stronger. This winter i had a few misfires which I attribute to the gas line antifreeze I added (HEET, I believe). I added a couple of bottles of Chevron Techron to clear up the lines (it was suggested by someone in another forum). I swear my engine felt stronger and it did help clean up the fuel. But I did not experience better gas mileage (I keep a notebook in my car to track mpg). If your Intrigue runs fine on 87 octane, then using 93 is a waste of money. If it makes you feel better, use 93 for every fifth fill up.

Now having said that, I don't buy the "top tier" vs. "cheap gas" argument. I live in southcentral PA (not to be confused with southcentral LA). This area is dominated by Sheetz, Rutter's, Turkey Hill. You would be hard pressed to find Exxon, Mobil, Sunoco, Shell, etc. (Haven't seen a Chevron station in about a decade). In our area, there is one distributor for all the gas.

I need hard proof that a) the additional additives that Shell, Amoco, Chevron add to their fuel are necessary and b) this "cheap gas" is bad for fuel lines and engine. BTW, a definition of "cheap gas" would be nice. My 2000 Intrigue has 144k miles and the last 5 tanks have averaged 27.5 mpg. I have never cleaned the fuel injectors and the current fuel filter has been on for about 80k miles. I did some searching on the internet and haven't been able to find these answers. I found tons of articles on Top Tier gas but nothing that says it is necessary for the average car? If I had a BMW or Mercedes then yes I would fill up with 93 octane at Exxon all the time. Instead I have a 8 year old car with 144k miles on it. I'll fill with the cheapest gas I can find and save my money for other things.

[Jimmy Olsen]

Originally Posted by dtownfb

Rolm: I have no doubts that your engine did feel stronger. This winter i had a few misfires which I attribute to the gas line antifreeze I added (HEET, I believe). I added a couple of bottles of Chevron Techron to clear up the lines (it was suggested by someone in another forum). I swear my engine felt stronger and it did help clean up the fuel. But I did not experience better gas mileage (I keep a notebook in my car to track mpg). If your Intrigue runs fine on 87 octane, then using 93 is a waste of money. If it makes you feel better, use 93 for every fifth fill up.

Now having said that, I don't buy the "top tier" vs. "cheap gas" argument. I live in southcentral PA (not to be confused with southcentral LA). This area is dominated by Sheetz, Rutter's, Turkey Hill. You would be hard pressed to find Exxon, Mobil, Sunoco, Shell, etc. (Haven't seen a Chevron station in about a decade). In our area, there is one distributor for all the gas.

I need hard proof that a) the additional additives that Shell, Amoco, Chevron add to their fuel are necessary and b) this "cheap gas" is bad for fuel lines and engine. BTW, a definition of "cheap gas" would be nice. My 2000 Intrigue has 144k miles and the last 5 tanks have averaged 27.5 mpg. I have never cleaned the fuel injectors and the current fuel filter has been on for about 80k miles. I did some searching on the internet and haven't been able to find these answers. I found tons of articles on Top Tier gas but nothing that says it is necessary for the average car? If I had a BMW or Mercedes then yes I would fill up with 93 octane at Exxon all the time. Instead I have a 8 year old car with 144k miles on it. I'll fill with the cheapest gas I can find and save my money for other things.

It sounds to me that the local brands you mentioned do a good of putting additives into their gasoline. Otherwise, I doubt that your Intrigue would be running as well as it is. You are also using after-market additives. Around Oklahoma area QT is a good brand of gasoline, rated Tier-one. You might want to find out what tier-one gasoline is all about. I have a friend with a '95 Blazer who just buys the cheapest gas he can find, the car runs very poorly, probably a blocked fuel injector(s).

Here are a link for you. There are others but they go to car forums which I'm not alllowed to post.

http://www.aa1car.com/library/bad_gas2.htm