misfiring/surging - bad gas possibly??

[AlienInv8r]

I went down to my buddies wedding this weekend, it was like 4 hours away to the middle of nowhere VA. Well anyways, my car drove beautifully the whole way down, but used up most of it's gas. I refilled the next morning at a shell gas station, but this is out in the country with not tons of use. Anyways, I put in maybe a half tank of regular 87 in my car. 10 minutes down the road it starts misfiring and surging when I throttle it and stuff like crazy. The SES light came on and blinks everytime it surges up a hill. On my way leaving, I had maybe an 1/8 tank left of that gas, I filled it up with 93 octane from a city (busy) station and added some of the STP fuel cleaner stuff. Well it still did the misfiring stuff the whole way home, and it's been doing it this morning also. I'm gonna get the code read at autozone later today to be sure of what this is. But does this sound like it was just a bad tank of gas?? I changed my plugs and wires like 3 months ago, so they're pretty much brand new. Also, how long does it take for the crappy gas to get totally out of the system? it's just getting annoying having this sputtering everytime I go up a hill or try to accelerate. Thanks.

[CamaroRob97]

sounds like plugs and wires and all that stuff.

[mcjoslyn]

It sounds like bad gas to me. I had the same problems one time after filling up on the Thruway at a station that was having construction done. It took me three whole tanks of gas before everything was back to normal. Don't worry about the higher octane, just get good quality gas and run a bottle of gas line antifreeze through each tank.

[AlienInv8r]

I don't think it's the plugs and wires since I just replaced them like in April. They dont go bad that quick. I went to Advance Autoparts, and they wont do the free OBD-scan. But the light finally went out, and it's starting to sputter less. I'm also just about out of gas, so I'm hoping this means it was definately the gas. I bought some more fuel system cleaner stuff, this X-R1 or something stuff. It looked like it was a step up from the regular additives, and said it helps improve sputtering and dirty fuel lines. Hopefully that, along with a few more tanks of clean gas will do the trick. I guess I learned my lesson, doesnt matter if it's a name brand station, out in the country it's risky to buy gas. On a positive note though, I did get great gas mileage on the way home, dunno if that was from the 93 octane or not, but it did get good mileage. But it seems like the problem is starting to clear up, hopefully all will go well. Thanks for the help so far, and I'll give a follow up if it goes away in the next day or so.

[HotWheelz]

That's EXACTLY the same thing mine just started doing a few weeks ago. My first thought was bad gas, but I couldn't figure out why it would only affect my car on the highway, and not in town. Did it affect yours in town or not? Even so, I tried dumping a bottle of additive in it to clean it up, but it hasn't helped as of yet.

Please let me know if you get the problem cleared up, because it might help me get mine fixed.

[AlienInv8r]

Mine is doing it in town and on the highway. I just tried a different additive in my tank tonight, I'll let you know how that goes. But as of now it's still doing it; Anytime I go up hill, or push it a little faster than normal it just starts to choke up. Hopefully it'll go away after a few tanks of gas, however the SES light just came back on again after I added gas. I'll keep you informed though, and let me know if you come up with anything either.

[HotWheelz]

For some reason, I can put my foot into it in town, and it won't choke up. That's what's confusing me. I'm going to have the 02 sensor checked as soon as I get a chance, and if it's not that, I'll probably try the plugs and wires next. Thanks for keeping me informed, and I'll do the same for you if I come up with anything.

[AlienInv8r]

I was looking through my Haynes manual today in the trouble shooting section, and under "engine misses throughout driving speed range" it lists a clogged fuel filter or impurities in the fuel system as the most likely cause of that. I'm thinking I may replace my fuel filter as it probably needs it anyways. But maybe that would get rid of the problem. Also under the "hesitation and stumbling during acceleration" section it lists the ignition system not operating correctly, or also dirty or clogged injectors. I doubt it's my ignition since those were recently replaced. But my most likely result seems to be a clogged fuel filter or injectors. I dunno if that gives you any ideas, but I'm gonna try replacing my filter and running a few more tanks of gas with injector cleaner in it.

[HotWheelz]

Im thinking I might try the fuel filter after i find out whether or not my 02 sensor is faulty. I know my fuel filter was changed well within the limits for one, but it might need it anyway. I'm going to do the same thing with the fuel injector cleaners to, because even if it's not the problem it certainly can't hurt.

[Coriya71]

DTC 400??? Cat ineffiency???

[HotWheelz]

I'd thought that maybe my cat could be starting to plug up, but I remembered what it was like when my old 84 Camaro had that problem, and this seems a lot different. But, it still might be worth a check if nothing else fixes the problem.

[AlienInv8r]

Anyone else have any ideas as to what this could be? Mine is going back and forth. From some lights I'll take off and it'll run just fine. I'll go to the next light and it'll be absolutely awful. If anyone has any ideas or similar experience, chime in. I'm still trying to figure this out. Thanks!

[MustangEater8251]

I say, pull the PCM IGN, and PCM BAT fuses, put them back in drive around liek a bat out of hell, use up the gas, and put more good gas in do nto worry about fuel system cleaners, maybe a bottle of that crap for water in the gas tank.

If it still does it pull the PCM ING and PCM BAT fuses again try again still doing it long after the gas is gone go from there.

[2brite99firebird]

mine was doing thgis and ended up being one of my coil packs and some was my fuel filtr also...hope this helps