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  1. #1
    Non-member Biggs's Avatar
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    Misfire off boost

    My engine has developed a misfire off boost to the point where it can cut out.

    It's kicking out a little black smoke when this happens.

    I've got a spare tdc sensor that I'm going to bang on there when I can muster some enthusiasm, what else can cause these symptoms ?

    Not sure wether or not I have a vacuum leak but that's another thing I will try to look at as the brake pedal idad really hard.

    Cheers for any input

  2. #2
    Non-member B18ftMOJO5's Avatar
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    Re: Misfire off boost

    Quote Originally Posted by Biggs View Post
    My engine has developed a misfire off boost to the point where it can cut out.

    It's kicking out a little black smoke when this happens.

    I've got a spare tdc sensor that I'm going to bang on there when I can muster some enthusiasm, what else can cause these symptoms ?

    Not sure wether or not I have a vacuum leak but that's another thing I will try to look at as the brake pedal idad really hard.

    Cheers for any input
    My b18ft did that the pipe on top of the egr pot. Goes into the inlet manifold had come loose. Made the car missfire like mad. And had no brakes. Pedal went really hard. Sorted now. I put a new bolt on and its ok.

  3. #3
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    I just removed the dump valve and connected vacume pipes and it seems to have done the trick. Going to take it for a blast and see if the problem comes back

  4. #4
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    Well that didn't cure it

    Had a monumental misfire today on the way to my bike training, which kind of naused up the day abit

    The car really struggled to get going, but then once i got the revs up abit and got it on boost, it cleared up and ran as normal.

    I've been putting off changing the TDC sensor as its abit of a pain with the chargecooler in the way, but looks now as though i'm going to have to get the tools out.

    Is there anything else you guys can think of that would be causing the problem ?

    Got to get this sorted as the car is my daily at the moment

    Cheers

  5. #5
    Non-member Matt@CodeRedMotorsports's Avatar
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    Re: Misfire off boost

    Try pulling the knock sensor off. Also the over boost connections.

  6. #6
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    Quote Originally Posted by Matt@CodeRedMotorsports View Post
    Try pulling the knock sensor off. Also the over boost connections.
    Over boost connections on F7p ? I didn't build the engine myself so not 100 percent sure if there are any

  7. #7
    Non-member Matt@CodeRedMotorsports's Avatar
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    Re: Misfire off boost

    Oops, skim reading again.......
    Was thinking C1J for some reason.

  8. #8
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    I have changed the TDC sensor now and its still the same

    Its really starting to annoy me now as i'm at the end of my mechanical know how.

    The only other thing i have noticed is that once the misfire clears, the revs are sitting high on idle( 2k as opposed to 800-1000)

    Anyone know where else i should be looking ?

    Forged F7p running a t28 i think,with a Pace charge cooler set up.

    Any help greatly appreciated guys, as i said this is actually my daily for the time being, so really need to try and sort this issue.

    Thanks

  9. #9
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    BUMP

  10. #10
    Non-member JRP's Avatar
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    Re: Misfire off boost

    Quote Originally Posted by Biggs View Post
    BUMP
    Should have bought my c1j forged lump.

  11. #11
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    Quote Originally Posted by JRP View Post
    Should have bought my c1j forged lump.
    I make you right there

  12. #12
    Non-member Brigsy's Avatar
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    Re: Misfire off boost

    Change the ignition components, dizzy cap, leads, plugs etc

  13. #13
    Non-member SCHWARTZ's Avatar
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    Re: Misfire off boost

    Black smoke is fueling related so check anything that could cause it to run rich and or not burn the fuel properly. What ecu are you using?

  14. #14
    Committee, South East Regional Rep James5's Avatar
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    Re: Misfire off boost

    Quote Originally Posted by Brigsy View Post
    Change the ignition components, dizzy cap, leads, plugs etc
    Was just going to say replace plugs and gap them properly. What ECU you using?? Sounds like running mega rich problem messing plugs up.

  15. #15
    Non-member Biggs's Avatar
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    Re: Misfire off boost

    AFAIK it's the standard R19 ecu, mapped to suit.

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