Octane

Discussion in 'The Garage' started by Will, Jul 5, 2015.

  1. Will

    Will Active Member

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    I normally run premium fuel but yesterday I filled up with regular gas and my engine was pinging pretty bad. I put some octane booster in today and it fixed it. I thought Mustang GTs can run regular without problems and only Cobras required Premium?
     
  2. mcglsr2

    mcglsr2 Well-Known Member SN95 Supporter

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    I regularly run my 95 GT stock engine on 87 with no problems. However, I also currently run stock timing (10*). I have noticed that if I try to increase the timing, it will periodically ping - but not constantly. I suspect, for a normal stock car, 87 is fine. If you start tinkering with things (like timing, long tubes, etc.), YMMV.
     
  3. Will

    Will Active Member

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    Well yesterday I did a hard launch in first gear and it sounded like marbles were in the engine. Basically really bad pinging and I looked in my rear view mirror and there was a cloud of dark smoke back where I first got the throttle. 2nd gear wasn't as bad but still pinged. That was the first time that's ever happened but I always run premium fuel. Also it was really hot outside so the air quality sucked. Fortunately after I put some octane booster in and did it again there was no issues. I've never checked the timing so I don't know if the previous owner advanced it. I googled pinging and it sounds like it could be carbon build up in the engine, too low octane, knock sensor going bad, dirty air cleaner, dirty MAF sensor, many things.
     
  4. ttocs

    ttocs Legend

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    by chance there wasn't a tanker there filling the gas station was there? Best advice I ever got was if you pull up at a gas station that has a tanker there hooked up, and there is a gas station across the street for 50 cents more per gallon, take the trip across the street. When they fill the tanks they stir up any sediment that might have ever made it into the tank and if you fill up while it is stirring the tank you can suck up damn near anything.
     
  5. 1998cobrasvt

    1998cobrasvt Well-Known Member

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    Thanks, good to know
     
  6. DropTopPony

    DropTopPony Administrator Staff Member Admin SN95 Supporter

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    Sea Foam time.....

    Not that I think it will help but the smoke show can be amazing :)
     
  7. ttocs

    ttocs Legend

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    might not be a bad idea to do a fuel filter swap.
     
  8. 96blak54

    96blak54 Legend

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    ^ good advise!

    Continual running a high octane not needed causes carbon build up inside the chamber. Switching to the lower octane will create more heat, dislodge carbon, and carbon not releasing will become hot spots in the chamber. Throw in a little bit of residual oil from pcv within the ports,... will multiply the situation.

    Seafoam it
     
  9. Michael Plummer

    Michael Plummer Active Member

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    If it doesn't detonate on premium fuel then run premium fuel.
     
  10. Will

    Will Active Member

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    Never used sea foam before. Will that stuff ruin your O2 sensors? Yeah that will be the last time I run regular.
     
  11. D3VST8R96GT

    D3VST8R96GT Well-Known Member

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    No it won't ruin the sensors

    Sent from my SPH-L720 using Tapatalk