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Thread: Injectors opening before cranking?

  1. #1

    Default Injectors opening before cranking?

    I was doing some datalogging of the TPS with key ON (engine not running), and noticed that injectors open (and stay open) at Cranking Fuel value whenever TPS returns below the Clear Flood TPS position. Fuel pressure was also bleeding down, indicating the injectors were open. What in the world would cause injectors to open at 0 RPM?

  2. #2
    Join Date
    Dec 2009


    Enabled Fuel Prime Percent in Engine Parameters? (Related Forum Post)
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    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/2800 RPM converter, M4602G aluminum driveshaft, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  3. #3


    Ya, I have that enabled. I thought it was basically a "batch fire" mode until cam sensor synced. Oh, I literally just understood as I wrote that.

    UPDATE: It's still showing injector pulse width after turning off the Enable Fuel Prime. My buddy is seeing the same with his car, but the fuel pressure doesn't drop. I'm guessing my fuel system is bleeding down back at the tank and it's not because the injectors are flowing.

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