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bad Gas leads to missfire....??

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Old 05-20-2012, 11:30 PM
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01FPGT
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Default bad Gas leads to missfire....??

So I should say it wasnt bad guess, but a dumb mistake by my bro who put 87 octane in my 01 gt when its tuned for 93. It ran like crap which lead to a CEL. Drove a few miles thinking it was just the gas and went home to siphon most of it out. I was able to and just burned off the rest. Now CEL came on and ran the code which read missfire in Cylinder #2.

I pulled plug and that was ok. I have new NGK plugs. I checked the Weapon X coil and nothing out of the ordinary. So I switched the coil to another position and wiped the codes. The car is driving a lot better but still has a small hesitation problem. Im hoping to get another CEL telling me missfire is in another cylinder so I can def know that its the coil. If not could it be the injector thats clogged? Can I pull the inj and clean it by spraying or blowing air into it? any suggestions or comments please let me know? I know some people have had issues with Weapon X coils...I do have the blue procharger 42LB injectors in there now.

Thanks for the help
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Old 05-21-2012, 11:29 AM
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Barley
 
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I had misfires due to old gas before. At first it was giving me codes for bad coils, when I checked them all it started giving me codes for misfires due to the spark plugs. Eventually, I started driving hard on a fresh tank, and magically they all dissapeared.
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Old 05-21-2012, 11:48 AM
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Derf00
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93 and 87 are worlds apart. Until you have every drop of 87 gone the code will probably stick around.

As long as you don't WOT while you still have 87 octane mixed in or get on it alot, it won't do any damage. It will just suck.

Probably take one or two tanks of 93 to get back to normal.

Don't have an 87 octane tune?
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Old 05-21-2012, 04:28 PM
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01FPGT
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Hey guys, no I don't, I used to before I got tune for the supercharger, for some reason my tuner didn't use my chip bank.. Ok I panicking bc I think it's my coils but I'm gonna head to the gas station and keep adding some fresh 93 octane .. I was worried bc I heard that weapon x coils were not the best..
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Old 05-22-2012, 11:20 PM
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so update..coil was not the problem, spark plug was. I pulled it and it was wet with oil on the threads and close to the tip. I dont think that is a good sign... I drove around after installing spark plug but im guessing the misfire will come back after a while of driving..
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Old 05-23-2012, 12:00 PM
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boduke0220
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Not good at all dude. Worst case scenerio the 87 made the car detonate so bad it blew the ring lands. what you should have done is parked it. drained the gas and put 93 in there and let it idle for like 30-45 mins untill the 93 was in the system
if you can get a light, take that plug out and look down in there which might be kinda hard or get a Q-tip ( with no loose stuff on it) and swab it and see how much oil was in there.

Last edited by boduke0220; 05-23-2012 at 12:03 PM.
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Old 05-23-2012, 02:54 PM
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thanks boduke, i did it last nite, there was enough to not drench the plug but there was residue along the threads..I have a feeling cylinder is screwed as well. well have to wait and see.
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