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87 Octane = P0300 *Misfire* ???

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GSXeclipsePSI

20+ Year Contributor
563
7
Jul 7, 2003
New Port Richey, Florida
Hey, got greedy and bought 87 Octance cause I was cheaper...

Well I'm guessing that since I put 87 octane *probley watered down* when I was on the empty light. So I'm driving and the car starts to act like BOOST Leaks. So as I drive the 40 miles round trip I had to go somewhere. I come home plug in my datatlogger and it tells me P0400 (6bolt swap EGR, MDP hooked up) and then the one I was waiting for P0300. Misfires on all 4 cycl. SO can someone tell me it was just the fuel causing the problem? I was out driving around last night without and issues it this only happend once I drove it today with the 87 octance. I also been switching from 93 to 89 to now today 87 only cause gas keeps getting cheaper and 2.99 loooked soooo good.

Please someone with answers, I feel like pulling the car aparts into peices right now. The plugs are new and the wires are older but only have a few grand on them. The coils are from the 1g motor that now have 90k on them. Coil on plug is my next upgrade.

Also car acted fine most of the time, it was a cruizing speed it would start pulling timing, but at points the car was take off like a bat out of hell... Only running 12psi since I had to remove my AFC Neo and take out my 550cc injectors and leave my walbro255 in until my refund check comes I can buy a new SAFC-2.

Thanks for your help I hope.
Kendel
 
Looking at your setup, it surprises me you would cheap out on the one most vital important thing that our car needs which is proper fuel. How did you get to where you are with such a mindset? Also I'm guessin you don't have an AFPR for your 255 Wally do you? Sell your car if you're going to be that much of a cheapskate. Hopefully someone else can take better care of it.
 
Look - don't go beating on your car if you only have $3 worth to put in your tank? way to consume more fuel while not having enough money to.

In all seriousness your car is running like crap because it's knocking because of the poor fuel. You could run 87... if you NEVER went into boost. keep your foot out of the throttle until you have money to run premium.
 
I'll admit I came off harsh at first and I apologize for that. But there should be no excuse for it. It says "Premium Unleaded Only" for a reason on the gauge cluster as well as the gas cap. And if you have come this far into tuning then you must also understand the concept of knocking and detonation and how timing works. There's just no excuse for it.
 
I was in the same predicament a few weeks ago. Tuscaloosa was out of premium (and pretty much gas in general) thanks to the hurricane hitting Texas. I was forced to put 87 in the tank, but knew the possible consequences. I bumped the boost down to 7.5psi and and babied the car for over a week. I don't think I saw any positive pressure through the duration of that half-tank.

The misfire code will go away when you get some higher octane fuel back in the lines. I haven't looked at your mods list, but if you are running a 255 pump with no AFPR you are likely over running the stock FPR.

.97 gallons and 1.05 gallons isn't a substantial enough gain to justify the potential problems you could have incurred.

You lucked out on this one. Go get some premium, driver around for a few miles, reset the ECU and you should be ok.

Goodluck!
 
well it runs fine now that I used the correct fuel. And I have many problems with my car that would be advoided if I had the funds at the time. I dont have a check book I have a small cash income. I did have a AFPR and its a crapped out one. Lots of shit got stolen from my car Im still working on getting a good running car for everyones info.

Even Apexi is a pain in the butt for making a AFC Neo that makes a crappy output signal.

I just wanted to make sure that I wasn't getting anything other problems then just the fuel, I no it was wrong. I have done clutchs to timing belts and everything but a engine and tranny rebuild so I raither not be told I'm stupid...
 
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