So a couple of weeks ago I put in a full tank of gas at Mobil. Since then the car has been idling very badly (idling at 1500 -2000) and is very hesitant from an idle. There is also a popping noise coming out of the idle, and a CEL came on. I checked the codes they are P0300, P0301, P0302,P0303, P0304, and P1399. Multiple misfires.

Could this be a case of bad gas? I never had a problem before filling it up. If it is bad gas, how do I get it out. I have near a full tank of gas in there. Thanks for the help.

Sri

 

check engine light?

 

Yes.

 

Hmm, everything was fine and now misfires on all cylinders. I would think bad gas could be a likely candindate. A Misfire can be caused by many things though. The dealerships usually start the troubleshooting process by ruling out bad gas anyway, so it seems it would definitely be the best place to start. Good Luck

EDIT: The CEL/MIL isn't flashing is it?

Old school syphon? I don't really know, never had to do it.

 

I doubt it's the case of bad gas since you had already run that tank empty and than filled it up with another full tank....right? If so than you can't be that unlucky to have 2 fill up with bad gas in a row. Check your spark plugs first to see if it rich or lean or if it going foul....that could lead to the misfired. Misfire cause by air and fuel not matching up. So, check your map but i lean toward the IAC. Take the iac out and clean it with wd-40. As for taking bad gas out of your tank....well, just use a long tube....stuck one end into the gas tank and then shuck it out with your mouth. Just make sure don't keep the tube stuck in your mouth once the gas is flowing through it

 

It's more than likely your injectors. Replace with new oem.

See this thread:

https://www.s2ki.com/forums/index.php?showtopic=292304

Very long...cliff's notes: bad injectors.

 

[QUOTE=negcamber,Jul 14 2007, 09:50 PM] It's more than likely your injectors.

 

Not sure what happens to the injectors, but it seems to be a cumulative effect over time to where they all start to go bad at about the same point. My car threw a code for missfire in 2 cylinders...and while waiting on injectors another started to throw a missfire. I had noticed that my idle was getting rough about a month or 2 before the codes.

Brand new oem injectors solved the problem.

Have not heard much about plugs or coil packs going bad on our car, but many have had the missfire lead to the injectors.

 

This same thing happend to me today!!!! I filled up on some gas from some place and in like 20 min the check engine light came on. Same exact codes P0300 P0301 P0302 P0303 P0304 And P1399. The place I used to fill up was a place that has switched to 10% ethanol. i dont know if thats the problem or not. I just know the same thing had happend to me today

 

Bad gas can definitely cause misfire codes.

I didn't read that you refilled with different fuel, so I'd start there. Save that fuel for the wife's car