Question about High Octane gas?

[NewChief]

Alright,

I've already caught grief for owning a Volvo V70XC, but it's the wifes. Anyway, the thing is knocking/pinging like crazy now. It only does it some of the time, and it does it sort of in time with the throttle: as you accelerate, so does the pinging.

I'm thinking this might be caused by the fact that it's hard as hell to get 93 octane fuel these days. Seems like I read somewhere that engine pinging is a common side effect of burning too low octane of a fuel in a car that needs high octane fuel. My mechanic looked at the underbody and didn't find anything loose. He's a great Volvo specialist, but he's also an eccentric nutcase, so I don't really want to ask him about it (or tell him I've been burning 91). Any confirmation?

[Radar Chief]

Yes, pinging is related to fuel. It’s also affected by air temp and load, that’s why you notice it coming and going. It probably runs better on cool days with some moisture in the air doesn’t it?
How many miles are on the engine? If you’ve got over 100K miles, you may have carbon build up on the piston crowns, which causes an increase in compression and could be causing your pinging.
Ignition timing will cause it also, if it’s been advanced.
Clogged injectors can cause it also, since this would produce a lean air/fuel mixture more prone to pinging.

[Saulbadguy]

http://www.starsovermississippi.org/images/garrett300.jpg
The washer fluid is NOT fine!

[HemiEd]

Yes, pinging is related to fuel. It’s also affected by air temp and load, that’s why you notice it coming and going. It probably runs better on cool days with some moisture in the air doesn’t it?
How many miles are on the engine? If you’ve got over 100K miles, you may have carbon build up on the piston crowns, which causes an increase in compression and could be causing your pinging.
Ignition timing will cause it also, if it’s been advanced.
Clogged injectors can cause it also, since this would produce a lean air/fuel mixture more prone to pinging.


Exactly, a lot of old tricks out there for supposedly removing carbon. I am not so sure how well any of them work. Used to see a lot of old farts putting a can of transmission fluid down the carb while holding the throttle far enough open to keep it running. It sure kept the mosquitoes away, not sure about the carbon removal.

[Otter]

Yes, pinging is related to fuel. It’s also affected by air temp and load, that’s why you notice it coming and going. It probably runs better on cool days with some moisture in the air doesn’t it?
It does, doesn't it!!! :Poke: Doesn't it!!! :Poke:

[PastorMikH]

I'd try pouring some high quality injector cleaner into the tank. The wife's car gets to pinging every now and then, this helps it.

Also, do you ever take the car out and open it up on the open road? It doesn't hurt them to run them hard once in a while. Dogging a car around town is a lot harder on them. Just don't oppen up the throttle around a state trooper.

[KC Kings]

Exactly, a lot of old tricks out there for supposedly removing carbon. I am not so sure how well any of them work. Used to see a lot of old farts putting a can of transmission fluid down the carb while holding the throttle far enough open to keep it running. It sure kept the mosquitoes away, not sure about the carbon removal.

I have seen old guys spray water from a cleaner bottle doen the carb. They said that also cleans the carbon off, but I am not suggesting that any put water down the carb.

[Radar Chief]

It does, doesn't it!!! :Poke: Doesn't it!!! :Poke:

http://tonova.typepad.com/thesuddencurve/images/kinnison.jpg

Come on SAY IT! SAY IT!!!

[JimNasium]

On related note I can buy super unleaded cheaper than regular unleaded here. I'm assuming it is because it is 10% ethanol. Is there any downside to fuel containing ethanol?

[Soupnazi]

That's strange. Modern vehicles have computer control which will retard the timing to stop pinging when you run inferior gas.

The fact that you're getting that, to me at least, the computer system isn't working quite right. AFAIK, no vehicles sold in the states are programmed to work with 93 octane only. You might try a couple of tanks running with an octane booster additive and see if it goes away.

[Radar Chief]

On related note I can buy super unleaded cheaper than regular unleaded here. I'm assuming it is because it is 10% ethanol. Is there any downside to fuel containing ethanol?

I personally don’t like it, but it seems to be running in a large number of vehicles just fine, so I’ll keep my yapper shut ‘bout it.

[JimNasium]

I personally don’t like it, but it seems to be running in a large number of vehicles just fine, so I’ll keep my yapper shut ‘bout it.
Not so fast mister. What is it that you don't like about it? I don't want to screw up the Jeepster. Help a brutha out.

[NewChief]

Yes, pinging is related to fuel. It’s also affected by air temp and load, that’s why you notice it coming and going. It probably runs better on cool days with some moisture in the air doesn’t it?
How many miles are on the engine? If you’ve got over 100K miles, you may have carbon build up on the piston crowns, which causes an increase in compression and could be causing your pinging.
Ignition timing will cause it also, if it’s been advanced.
Clogged injectors can cause it also, since this would produce a lean air/fuel mixture more prone to pinging.

Sounds dead on. Definitely over 100k miles. I'll talk to my mechanic about it. Thanks for the advice.

[Radar Chief]

Sounds dead on. Definitely over 100k miles. I'll talk to my mechanic about it. Thanks for the advice.

No problem, hope it isn’t too expensive to remedy.

[Radar Chief]

Not so fast mister. What is it that you don't like about it? I don't want to screw up the Jeepster. Help a brutha out.

Damn, couldn’t sneak out fast enough. ;)

Iowanian, Htis and I have gone ‘round ‘bout this before, that’s why I mentioned keep’n my yapper shut.
I don’t like it because it is corrosive to aluminum and magnesium, which is being used more often in the search for smaller more powerful engines. It can also swell or deteriorate rubber o-rings, which are all over your injection system.
They like it because it helps farmers, since it’s made from grain, and it supplements the fuel we buy from the ME. I agree with there reasoning, but I still don’t like the stuff itself.
I guess if it’s work’n for ya fine, but I’ll still avoid it.

[HemiEd]

On related note I can buy super unleaded cheaper than regular unleaded here. I'm assuming it is because it is 10% ethanol. Is there any downside to fuel containing ethanol?

I like the ethanol (domestic product from farms) in fuel for late model fuel injected cars since most of the seals were designed to handle it. In carbed motors, it will dry out the gaskets when it sets a while.

[Radar Chief]

I like the ethanol (domestic product from farms) in fuel for late model fuel injected cars since most of the seals were designed to handle it. In carbed motors, it will dry out the gaskets when it sets a while.

There ya go, I was just 'bout to ask what you thought.

[HemiEd]

There ya go, I was just 'bout to ask what you thought.

Radar, I actually look for the stuff when putting fuel in my 300 or Durango. Kind of gives me the warm fuzzies like I am doing something good. I avoid it with my old cars and boat though. We have a station down the street that sells 110 octane leaded fuel from a short hosed pump. The Barracuda really likes that stuff!

[Skip Towne]

Damn, couldn’t sneak out fast enough. ;)

Iowanian, Htis and I have gone ‘round ‘bout this before, that’s why I mentioned keep’n my yapper shut.
I don’t like it because it is corrosive to aluminum and magnesium, which is being used more often in the search for smaller more powerful engines. It can also swell or deteriorate rubber o-rings, which are all over your injection system.
They like it because it helps farmers, since it’s made from grain, and it supplements the fuel we buy from the ME. I agree with there reasoning, but I still don’t like the stuff itself.
I guess if it’s work’n for ya fine, but I’ll still avoid it.
I wish we could make 100% of our fuel from corn. Then we could tell the A-rabs to go to hell. That would be sweet.

[teedubya]

http://tonova.typepad.com/thesuddencurve/images/kinnison.jpg

Come on SAY IT! SAY IT!!!

Damn, I miss Kinnison...
Damn, I miss Hedberg...
Damn, I miss Hicks...

funny ****ers, quit dying. Damn.

[teedubya]

I wish we could make 100% of our fuel from corn. Then we could tell the A-rabs to go to hell. That would be sweet.

especially if it was sweet corn, huh? personally, Id like Hemp to be the fuel, like Mr. Henry Ford created back in the mid-30's.

[augustorm]

I am new here, but this thread is pretty important.
We don't want anyone to destroy their rides by experimenting.
Though pinging (pre-detination) can be related to fuel, it isn't always the case....In your case. It is not as far as the octane level is concerned. 91 is sufficient for all stock cars. It is even okay to run 91 octane in cars that have performance chips (Even though the chip makers say to run 93 or higher).
I have a 2003 V-6 mustang that has been bored and stroked from its orig. 3.8L to a 4.3L. It has a Procharger supercharger pushing 11Lbs of boost and guess what? It runs perfect with 91 octane. So my point is....it is not the octane level....You have another problem....could be the carbon buildup....could be your fuel system. So yes, have your specialist look at it. Also I am assuming this thing is fuel injected. The only way to clean the system is to hook it up to a pressurized system. Most of your oil changing places have this system and it works. Adding a fuel additive is like using liquid plummer on a clogged drain...GOOD LUCK!
Remember...the amount of octane is related to only one thing....the amount of compression you are runnig. Higher octane gases will handle higher compression engines. Since the compression on your engine has not changed, there is no need to up the octane amount.
Hope this helped.

[PastorMikH]

Not so fast mister. What is it that you don't like about it? I don't want to screw up the Jeepster. Help a brutha out.



JimN, it's not like you went for quality in the first place. After all, it is just a jeep.


:Poke:

[Calcountry]

http://tonova.typepad.com/thesuddencurve/images/kinnison.jpg

Come on SAY IT! SAY IT!!!ROFL

[JimNasium]

JimN, it's not like you went for quality in the first place. After all, it is just a jeep.


:Poke:
Don't you have some people to be nice to somewhere?

[stevieray]

Don't you have some people to be nice to somewhere?

Only if they drive Landcruisers.