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P0430 Code 100 miles after resonator delete, and higher octane fuel

malibu7899

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Good morning, everyone. So, like it says in title i bought my Mustang GT used with 11,500 miles on it. So i do not know what type of fuel the previous owner used during owner ship. The best fuel I have available to me is 91 Non ethanol which I have used since buying and car currently sits at 13,600 miles. In the last 100 miles I installed Steeda H pipe resonator delete. and I went online and checked with a fuel blend site to see what I could do to reach 93 octane for a tank and just see if the car likes it. So I added 2 gallons of 110 fuel and 14 gallons of 91 to theoretically get me right around the 93 octane number. Now within the first 100 miles i had a p0430 code, and I thought maybe the car just hadn't adjusted maybe to the different fuel, so I cleared the code and it came back on within 30 miles. Just seeing what you guys might think. Did the fuel smoke a oxygen sensor, or is the cat starting to fail? The plan is to run the rest of the fuel out and fill back up with 91 again and see what happens before I make a appointment with the dealer. Just curious on everyones thoughts or if they have seen this. Thanks, Jason.
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erocker

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Bad cat on bank 2. Were you running the fuel pump a lot without starting it?
 
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malibu7899

malibu7899

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No, not at all. I had a 1/4 tank of 91. Filled 2 gallons of 110, started it and drove 150ft forward to the 91 pump and topped it off. Started it and whet on my way like normal.
 

Fender5803

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I'm thinking it might be OK with 91 oct ? Maybe drain the tank ?
 


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malibu7899

malibu7899

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Just talked to the station and they said it does contain lead. So, I am going to try and transfer the fuel out and use it in my 78 Malibu and fill back up with 91.
 

rbeyer

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If it was leaded you may have fouled the sensors, hopefully the cats are OK, but don't run it until the system is fully drained. Might be an expensive experiment.
 

5.DREW

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I’ve been having the same issue now for almost 2 months and the dealer claims the cat is on back order with no ETA. Car is completely stock not even a resonator delete
 
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malibu7899

malibu7899

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I wonder if the cats are different for the Dark Horse. It appears that the resonator has different part numbers for GT vs Dark Horse. I had just been looking up oxygen sensors for the car.
 

GregB-Dark-Horse

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Was that Leaded fuel.
Yeah I'm thinking the same if it was 110 race fuel, if it was unleaded race fuel then you should be good.

Otherwise you said you did the Steeda H-Pipe resonator delete, maybe you damaged a wire to the O2 sensor during the install and/or it's now touching the pipe?
 
 








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