I knew that was coming. Nice post! 
What would bad gas do?
Thread Starter
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
What would bad gas do?
The car has been running very good lately and a new symptom started occuring yesterday.After I filled up the tank with Sunoco 93 I developed a stumble.It only occured at light throttle under load.The symptoms were similar to the knocks I was getting when my EGR was bad.
The FSM says to check the fuel first in the flow chart so I picked up a bottle of Techron and took a ride.It has improved since I put the cleaner in and I will go for a longer ride later to use up the fuel.Now obviously if the problem goes away it is a tank of bad gas.
My question is what can be wrong with the gas?What can cause an engine to knock with a bad tank?What other things or symptoms can occur with bad gas.This is a public service thread.
The FSM says to check the fuel first in the flow chart so I picked up a bottle of Techron and took a ride.It has improved since I put the cleaner in and I will go for a longer ride later to use up the fuel.Now obviously if the problem goes away it is a tank of bad gas.
My question is what can be wrong with the gas?What can cause an engine to knock with a bad tank?What other things or symptoms can occur with bad gas.This is a public service thread.
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
Man gone through same problem yeserday, i usually get gas from shell or exxon 93 , but running out of gas on hwy so filled up with citgo 93 and after 20 miles oil temp gone to 240, and stumble and also oil pressure dropped to 25-30 dont know what causes gas or my oil temp/pressure sensor?. But increase little fuel pressure with AFPR so it helps little bit and oil pressure back to 55-60 looks ok but still scared to drive though,
Our cars need good fuel 93 octane, period.
just few mins ago fired the car, temp says LO and oil pres stays 55-60 supposed to be 80 but its alright iam gonna drop some octane booster.
I know i did not pass good tech reason for ur problem, but similer problem gone through so the story. Some tech info should chime in, more info please.
Our cars need good fuel 93 octane, period.
just few mins ago fired the car, temp says LO and oil pres stays 55-60 supposed to be 80 but its alright iam gonna drop some octane booster.
I know i did not pass good tech reason for ur problem, but similer problem gone through so the story. Some tech info should chime in, more info please.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Can't give you a tech reason, but water in the gas will cause all kinds of bad things. Bad only in the sense that it is correctible in most cases. Hopefiully, it isn't a tank of bad gas as in dirty, really dirty, that would clog the fuel filter, which I doubt.
As far as dry gas goes, I'd use a couple, serially. And get the iso dry gas vs. the meth. It mixes and burns. (by Heet, it's the red bottle vs. the yellow bottle).
Once, on a trip, I got a bad tank of gas (had bad tanks of gas when not on trips, too) and stopped at a garage in Wisconsin. It was so bad that I barely made it up a very gradual hill to a garage. Garage suggested it might be something as simple as a bad tank of gas and said put in two bottles (a lot for a 13 gal. tank) and see if it helped. Put in the two bottles, and within five minutes things were back to normal. Ran that tank down to about 1/4 and filled up (thankfully) with good gas.
Hope it's something this simple for you.
As far as dry gas goes, I'd use a couple, serially. And get the iso dry gas vs. the meth. It mixes and burns. (by Heet, it's the red bottle vs. the yellow bottle).
Once, on a trip, I got a bad tank of gas (had bad tanks of gas when not on trips, too) and stopped at a garage in Wisconsin. It was so bad that I barely made it up a very gradual hill to a garage. Garage suggested it might be something as simple as a bad tank of gas and said put in two bottles (a lot for a 13 gal. tank) and see if it helped. Put in the two bottles, and within five minutes things were back to normal. Ran that tank down to about 1/4 and filled up (thankfully) with good gas.
Hope it's something this simple for you.
Team Owner
Joined: Feb 2005
Posts: 20,111
Likes: 1
From: My redneck of the woods louisiana
i got a bad tank of gas from a very popular mobil station here and it caused all sorts of weird behavior. it idled bad, when i stepped on the gas it would hesitate real bad and feel like it was bout to die, had no power for merging/passing and it was an awful 2 weeks
edit: i also got about 8 mpg
edit: i also got about 8 mpg
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Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
very typical of water in their fuel-water in fuel resembles little marble-between my daughter and I we got 3 bad tanks in the past year-even the media was reporting it. 76 was even paying for injector cleaning.
GET Heet or is it Heat fuel treatment-works good.
GET Heet or is it Heat fuel treatment-works good.
