Is there such thing as a bad tank of gas?

[happy2B5]

If so, GOD I hope that is all that happened to me. I know hope in one hand and shit in the other, but my car did some crazy shit yesterday. And to top it off all during socal Friday afternoon traffic. The car completely stopped moving not once, but three times on the freeway(s). And not one damn check engine light. It fealt like the worst charge pipe misfire ever. I let it sit each time and when I would finally get it to idle it was rough as hell and would not rev (totally fuel starved) then viola, it would fire up and smooth out and I'd be on my way again. 3 times this happened. I know scan and check back, but jeezus that was not cool sitting along LA freeways stranded. I don't know if it was just me hearing every little abnormality, but my fuel pump sounded louder than usual? Today not so much.

And on the way home today (~250 miles) - not one symptom similar to yesterday!?

The car is stage 3 - ko4's, vast fueling, fuel pump, log manifolds w/spacers, true dual 2.5 tt exhaust...
Could it really have been a bad tank of fuel? Car acted completely normal until I filled up and somewhat normal until I got into stop-go traffic.

[viceprp]

If you see a fuel truck in the gas station, pack your bags and leave.

If the owner of the gas station is Indian, pack your bags and leave.

If they sell funky glass bottles that say "tobacco use only", pack your bags and leave.

[happy2B5]

it is difficult to find a gas station in my neck of the woods that is not...all the above :)

[GTAnimal]

Yes bad gas is all over the place. Ive even seen cars pull into our shop that had diesel in the tank but it came out of the 93 octane nozzle!!! I only get gas at a few stations around town. If it looks sketchy it probably is. But you hit it on the head, run a scan and let us know what you find. Hope its just bad gas

[Stubek]

At least with the B8, Audi recommends top tier gas only which is Shell, Unical 76, I think Mobil and Chevron. I know Arco and BP are not on that list. You can see the full list and description of Top Tier here http://www.toptiergas.com/retailers.html

If you have new gas and the problems went away, then yeah, it was probably bad gas. If they don't go away or they come back with your "normal gas" that you get, then check the usual stuff such as plugs/gaps, coils, fuel filter.

[howardfootball]

I've had this happen before when I filled up at a different station when on a trip and all the symptoms went away when I filled up at my regular station.

[happy2B5]

At least with the B8, Audi recommends top tier gas only which is Shell, Unical 76, I think Mobil and Chevron. I know Arco and BP are not on that list. You can see the full list and description of Top Tier here http://www.toptiergas.com/retailers.html

If you have new gas and the problems went away, then yeah, it was probably bad gas. If they don't go away or they come back with your "normal gas" that you get, then check the usual stuff such as plugs/gaps, coils, fuel filter.

It was a shell station btw...gonna scan monday, time for smog anyway. need to make sure all is a go before the inspection.

And if all checks out, what is my best defense or follow-up procedure to make sure all that crap is cleared out of the car now?

[2.7taudi]

It was a shell station btw...gonna scan monday, time for smog anyway. need to make sure all is a go before the inspection.

And if all checks out, what is my best defense or follow-up procedure to make sure all that crap is cleared out of the car now?

Change the fuel filter.

[S4James]

i put a bad tank in once.

blew my #5 cylinder 20miles later.

and there is nothing I can do about it either.

[AudiA4_20T]

Change the fuel filter.

Yup. Bad gas to me is the LAST symptom on a large list that I'd consider

[happy2B5]

point taken. thing is the fuel filter has been replaced within the last 3-4k miles. I was thinking my "hi flow" fuel pump was taking a sh.t on me.

[bassmek2]

What exactly is the problem ur having

Sent from my LG-P999 using Tapatalk 2

[bassmek2]

Excuse that last post didn't realize there was more pages this tapatalk confusedd me

Sent from my LG-P999 using Tapatalk 2

[happy2B5]

only code was a p1556 - probably due to my torn tbb (now replaced).

hope I escaped with an isolated incident of crap gas...fuel filter replaced as precaution - was flowing clear, nothing abnormal.
only difference between the last few tank fulls has been prior to fuel filter replacement was that preceeding tank of gas. Car is running normal without a glitch (never say that!)

[MikeyB3]

What particular station did you get fuel from? I've come to find that mine likes Shell, Sunoco, and 76. I burn through Chevron like it's water, and Mobil gets me horrible mileage. I wont even consider BP or Arco (BP).

Conversely, I have a 150cc scooter that I fill up, and it likes Chevron. Go fig.

[happy2B5]

it was shell branded but not a typical station i stop at regularly. this happened during a mini road trip to socal (~250 miles). Car was fine before I stopped and then stranded me 3 different times once i got into LA traffic. pretty much ran the tank empty and refilled. no problems getting home or after the fact. i use shell as much as any...i too have noticed mobil yields me worse mileage, also costco gas while cheaper on the wallet gets terrible mileage. gas prices are crazy out here especially considering the shit product we get.

just a simple google search and some more digging around i found that if the pump is moving very slow (mine was) it is an indicator the underground tanks are low on fuel and/or thier pump filters are clogged and junk. also, where i live, the station owners are buying and filling the tanks as little as possible (cheap bastards). if i were to have bought a tank of fuel from the bottom of their tanks, where does any water settle out, the bottom. too much time and refills have come and gone for me not to conclude i got a bad tank full at this point.

[AudiSportB5S4]

Might as well mention here that gasoline degrades pretty quickly... I have a very tuned car with a bunch of timing for the alcohol that I run and if I let the car sit a week without starting it that fuel in the tank will cause higher knock and ignition retard than a fresh tank of 93.

[happy2B5]

good point. this car is a weekend warrior. does not see the road much throughout the week and is prone to sitting in the garage for stretches.

[MikeyB3]

good point. this car is a weekend warrior. does not see the road much throughout the week and is prone to sitting in the garage for stretches.

Just remember that when you know it's going to be sitting, just dont have it sitting with a tank full of fuel. If it were me in your position, try and find a station with some 100 fuel, maybe run it down and put some spicey fuel (2-3gal) in there, attempt to clean it up. I do not suggest putting a tankful in. I did that one time, I think it was 100 or 104 fuel, cost me 115$ to fill up. Never again.

[Monty23]

Does sta-bil fuel stabilizer affect octane or anything? I always use Sunoco gas stations....

[waB5S4]

What particular station did you get fuel from? I've come to find that mine likes Shell, Sunoco, and 76. I burn through Chevron like it's water, and Mobil gets me horrible mileage. I wont even consider BP or Arco (BP).

Conversely, I have a 150cc scooter that I fill up, and it likes Chevron. Go fig.

I've always considered Shell and Chevron to be top tier but Chevron > Shell. I used to only put Chevron premium in my last car and it loved me for it.. The S4 is a bit of a different beast though, must be the specific additives but it MUCH prefers Shell > Chevron.

Like the quote above, the S4 pounds Chevron back like its water so I try to stick to Shell.

[Scotty@Advanced]

I'd change your fuel pressure regulator, they have been known to stick open or closed which can cause all sorts of funky behavior and generally it won't last long enough to throw a code. Also the FPR is relatively inexpensive and easy to change.

[happy2B5]

I'd change your fuel pressure regulator, they have been known to stick open or closed which can cause all sorts of funky behavior and generally it won't last long enough to throw a code. Also the FPR is relatively inexpensive and easy to change.

thanks for more possible solutions Scott

[S4 00 2.7]

Im going to try Shell more often. I think my car likes 76 as well.

[JackalS4]

You should also double-check any possible fuel pump electrical connections/grounds if applicable and make sure all looks good and snug.

[JmanEspresso]

Im curious where most people fill up.

For me, its only Shell 93. Used to use Sunoco 93, but switched to shell a while back. When I learned that Audi reccomended Shell gas for their cars, at least for the handful of Audi's we've owned, turbo and N/A, I never used anything else.

Nowadays, if its an emergency, and I cant find Shell, Mobil or Sunoco will do, but like I said. Shell.

[happy2B5]

You should also double-check any possible fuel pump electrical connections/grounds if applicable and make sure all looks good and snug.

check and check...will do

[S4 00 2.7]

Im curious where most people fill up.

For me, its only Shell 93. Used to use Sunoco 93, but switched to shell a while back. When I learned that Audi reccomended Shell gas for their cars, at least for the handful of Audi's we've owned, turbo and N/A, I never used anything else.

Nowadays, if its an emergency, and I cant find Shell, Mobil or Sunoco will do, but like I said. Shell.

Shell or 76.

I used to go to Chevron once in a while but I will go there less now.

[AudiNFS]

Im curious where most people fill up.

For me, its only Shell 93. Used to use Sunoco 93, but switched to shell a while back. When I learned that Audi reccomended Shell gas for their cars, at least for the handful of Audi's we've owned, turbo and N/A, I never used anything else.

Nowadays, if its an emergency, and I cant find Shell, Mobil or Sunoco will do, but like I said. Shell.

Did not know Audi recommended Shell. My closest Shell is 30 minutes away. I'm forced to use Sunoco, but have never had any problems with it.

[Turtle]

thanks for more possible solutions Scott

DUDE! Your in Califonia.... We have nothing BUT bad gas. Cali gas is complete and utter shit. Honestly, I've considered running only Streetfire 100 oct... but at almost $9/gal its not feasible.

[AudiMike70]

sounds like a bad tank of gas! put some dry gas in ur tank and run it down as low as u can b4 you fill up somewhere else!!! good luck!!!

[happy2B5]

DUDE! Your in Califonia.... We have nothing BUT bad gas. Cali gas is complete and utter shit. Honestly, I've considered running only Streetfire 100 oct... but at almost $9/gal its not feasible.

Ya, believe me I know...obviously this incident was something more than the crap detergent rich, low octane variety (IF it was just a bad tank). Can't wait to leave this cest pool...if not only for better gas options for my Audis

[Turtle]

Ya, believe me I know...obviously this incident was something more than the crap detergent rich, low octane variety (IF it was just a bad tank). Can't wait to leave this cest pool...if not only for better gas options for my Audis

WERD!

[Sp8t]

Think I might be a victim of a bad tank of gas...Went to Chevron yesterday with just under a 1/4 tank and filled up with 91 and fired her up and about 10 feet away from the pump, she started to run like hell!!! Went home and got the following codes... My buddy gave me some Lucas octane booster and some stabilizer so I put it in and rocked the tank as much as possible. I then fired her up and she started just like I left her (crap). 15 seconds later or so she smoothed out and ran perfect. I proceed to high five the wife as she was watching me do this and not but 1 second after I did that my car went back to crap mode again...Should I drain this tank and fill her up with some new??

[MikeyB3]

Think I might be a victim of a bad tank of gas...Went to Chevron yesterday with just under a 1/4 tank and filled up with 91 and fired her up and about 10 feet away from the pump, she started to run like hell!!! Went home and got the following codes... My buddy gave me some Lucas octane booster and some stabilizer so I put it in and rocked the tank as much as possible. I then fired her up and she started just like I left her (crap). 15 seconds later or so she smoothed out and ran perfect. I proceed to high five the wife as she was watching me do this and not but 1 second after I did that my car went back to crap mode again...Should I drain this tank and fill her up with some new??

I'd just figure out a way to run all the gas out, without boosting. Then, dont go to Chevron. I'm not far from you, but I run 76 and Shell religiously and never had a problem. Mobil and Chevron both make the car feel like complete shit. You can hear it, you can feel it--- never again.

If you really wanna help it out some, drive a bit, then throw a few gallons of 76s 100 octane, and let it even out.

[Sp8t]

I'd just figure out a way to run all the gas out, without boosting. Then, dont go to Chevron. I'm not far from you, but I run 76 and Shell religiously and never had a problem. Mobil and Chevron both make the car feel like complete shit. You can hear it, you can feel it--- never again.

If you really wanna help it out some, drive a bit, then throw a few gallons of 76s 100 octane, and let it even out.

Great advice!!! Thank You MikeyB3. I am kinda timid right now to even drive her at all due to incredible poor and rough idle...I am on board with 76 and shell after seeing this post. I would seldom use anything other then Chevron for the last 10 years but have no problem changing it up based on all the useful info I am seeing here including your response. I will try your suggestion pending I can handle not freaking out while driving. lol. I was going to Siphon it out but I have nowhere to put 15 gallons of shit gas...

[rockcandy]

We have great gas here where I live! I feel bad for you people that can't get the good stuff.

[Sp8t]

We have great gas here where I live! I feel bad for you people that can't get the good stuff.

I have never had this issue before. But am enlightened now.

[MikeyB3]

Great advice!!! Thank You MikeyB3. I am kinda timid right now to even drive her at all due to incredible poor and rough idle...I am on board with 76 and shell after seeing this post. I would seldom use anything other then Chevron for the last 10 years but have no problem changing it up based on all the useful info I am seeing here including your response. I will try your suggestion pending I can handle not freaking out while driving. lol. I was going to Siphon it out but I have nowhere to put 15 gallons of shit gas...

Hey, not a problem man. I ran into this problem in New England once when some attendant wouldnt let me pump my own gas, and then filled it up with 87 when I explicitly said "93, premium, please." I had some very cross words with him, but then left and insisted I pumped my own gas when I came back. Just get some top notch fuel in there ASAP. You'll be fine. Avoid boost til you know there's some good fuel in there.

hit me up if you're ever close to Santa Monica.

@rockcandy: do you live in the area of OK where they dont use ethanol? I went through there on my trip to CA, and I was thrilled that it was 100% fuel. Mmmm.

[ilyafil]

Think I might be a victim of a bad tank of gas...Went to Chevron yesterday with just under a 1/4 tank and filled up with 91 and fired her up and about 10 feet away from the pump, she started to run like hell!!! Went home and got the following codes... My buddy gave me some Lucas octane booster and some stabilizer so I put it in and rocked the tank as much as possible. I then fired her up and she started just like I left her (crap). 15 seconds later or so she smoothed out and ran perfect. I proceed to high five the wife as she was watching me do this and not but 1 second after I did that my car went back to crap mode again...Should I drain this tank and fill her up with some new??

Did you ever check you fuel press?

On a side note: Where I live all gasoline is the same. It all comes from the same refinery right here in town. I have watched a Chevron truck, a no name truck, Shell, Arco and so on. All fill up from the same rack. I'm sure it's the same everywhere else. Some station owners don't maintain their equipment so they get a bad rep. It's not bad gas, it's bad gas stations. Too bad 93 isn't readily available here. E85 is, though!