Engine idle issue

[dsmBear]

Okay so today i went to arco gas station and put 25 bucks in the tank of premium 91. I already had about an eigth of a tank. By the time i drove about 15 miles, my engine started to idle weird. My air fuel says its running rich and it spits water out the exhaust. It has a weird little misfire thing going on but its not 100% of the time. I put some octane booster in and it hasnt done anything yet. It just threw a p0301 code and im getting concerned. my buddies at work tell me that i shouldnt use arco gas because it is watered down. It adds up, but im just getting the dsm tuners opinion because you guys always have the right idea. They said arco just started using a winter brew. Should i just drive off this tank and put chevron in it and clear the code? I need help. Please and thank you. Btw i dont know if this helps, but when i rev the engine, the exhaust pops a little.

 

[hondo0975]

I have a 1g an if it were me an i thought it was just bad gas i would drain it an put fresh gas in from a gas station that has proven to not give me issues. I say i have a 1g because i have a drain plug for my gas tank im hoping the 2g does as well. For me i always use the same gas stations for my vehicals. I have one near work an one near home thats all i use unless im travleing. Hope this helps u. Good luck.

 

[WES_393]

By "air fuel" do you mean Wideband or narrowband? Is it rich at idle or wide-open?

If it were bad gas, some Seafoam in the tank right before filling up at a different station would solve the problem. However, it sounds like a huge boost leak to me such as a coupler popping off. It would just be coincidental that it happened right after you got gas making you think it's the gasoline.

 

[ThunderChild]

you can test the gas to see what its alcohol content is pretty easily. get a graduated cylinder and fill it to 100 ml with your gas. then pour 10 ml of water in. carefully cap the cylinder with your hand (wear gloves!) and shake for about 30-45 seconds. then let sit for 1-2 minutes.

the alcohol will absorb into the water and settle at the bottom of the cylinder. whatever the amount is in ml thats the percentage of acohol content. (dont reuse this gas)...

it could be winter blend, could also be an ignition issue. do a spark plug test, wire test, coil test...check base timing.

 

[hondo0975]

Just curious as to what you found out was causing your problems?

 

[93AWDDSM]

am pm/arco gas sucks, whenever I would put that in my tsi on WOT it would slightly hesitate throughout the rpm. When I use Chevron its a smooth pull throughout the rpm range with constant normal idle. Sorry but I honestly think its the quality.. frown upon this if you must, to each their own.