Old Gas

[Justin]

How long can gas sit in your tank before it starts to degrade?

Also, would bad gas cause a really poor power/boost ratio, and cause a rough idle and an occasional miss?

What I mean by poor p/b ratio: I'll be full throttle with a mid 11 afr and 9 PSI and it just feels SLOW. I don't really seem to be going anywhere....




I'm going to go fill the tank soon but I developed a coolant leak so I can't go anywhere yet... I'm just asking in the meantime.

 

[Sawbladz]

Off the top of my head I think gas can sit for ~3 months. I will try and verify that.

EDIT: 2 months from a source online...

 

[Justin]

Off the top of my head I think gas can sit for ~3 months. I will try and verify that.

EDIT: 2 months from a source online...

Well that's neat! Maybe that's the cause of the poor running conditions, seeing as I have no more codes to get rid of.

I'll hurry up and fix my coolant leak, then get some fresh gas in her!

 

[Poodles]

depends on the grade, and what the mix is...

most fuels now use ethanol as the octane additive, and it will evaporate quickly.

do you also have a properly functioning charcoal canister?

 

[Mr.PFloyd]

Which is why i shall buy octane booster woop woop!

 

[Poodles]

octane booster won't raise octane enough...

 

[cml61386]

If there is a high alcohol content this will cause the car to run poorly. Take a sample of fuel and mix it with water, wait till it settles out. Mark the water line then add more fuel if the water line moves higher than what it was. You had alcohol in ur fuel. Too much alcohol can cause driveability issues with the car or the driver.

 

[jdub]

^^^ Not too sure where you come up with that one...the alcohol content would have to be a pretty high percentage.

If you want to raise the octane on pump gas, read this thread...all of it:
http://www.supramania.com/forums/showthread.php?t=17442

 

[Justin]

well i found the coolant leak so i'm going to get that taken care of tomorrow and fill up the tank to avoid speculation.

I don't have a charcoal canister, its just vented down by the frame rail. the car has been sitting for about 7 months.

I sure hope its the gas :-D

 

[americanjebus]

Yea my car has been sitting for like ~ 6 months too on a full tank. I have a 6 hour road trip to bring it back to my place so im going to add about a gallon of race gas and injector cleaner for the trip. Then refill on 92 oct. and plugs.

Figure a gallon or two of 114 oct. will help regain that little i lost over winter.

Not to thread jack but would shitty 6 month old gas give inaccurate AFR readings say if i was tuning lo and mid load settings? less than ~150kpa

 

[Poodles]

dunno about the AFR's, but if your tank is just vented without some evap. recovery system, you'll lose parts of the fuel mix (like the ethanol I mentioned).

Could very well be the gas in your case, if it was a full tank and the system wasn't vented, you might be better off...

 

[Push]

my cars been sitting for 2 years on 93 octane... Gas tank is half... should i be worried this summer when I start it up?

 

[cml61386]

^^^ Not too sure where you come up with that one...the alcohol content would have to be a pretty high percentage.

If you want to raise the octane on pump gas, read this thread...all of it:
http://www.supramania.com/forums/showthread.php?t=17442

I was working on a car that had driveability concerns, so thats what an engineer told me to do. To check and make sure there wasn't alot of alcohol content because alcohol absorbes water which doesn't make a car run very well. I've also been told that a car with a full tank of gas is alot better off than 1/4 tank or less. I would imagine that would apply to a system with a full funtional EVAP system.

 

[bgrieger]

my cars been sitting for 2 years on 93 octane... Gas tank is half... should i be worried this summer when I start it up?

When I had the tank redone years back I saved the 1/2 tank for the lawnmower...it wouldn't start on the stuff after about a year and a half without a can of ether to get it rolling. I wouldn't try that with my car if I were you...

 

[screaminglemon]

heres a question. where the heck can you get rid of the old gas?

 

[TuRbOdReAmZ87]

^^^ poor that shit on the ground. lol :sarcasm: