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Thread: Terminator X Max VSS Issue

  1. #1

    Default Terminator X Max VSS Issue

    Having an issue with my Terminator X Max. Had everything working great for a couple weeks in my ‘56 Chevy. Speedo was working perfect everything dialed in great, then this issue came up. Speedo MPH bouncing around while driving, sometimes will go all the way to 120 MPH and stay there. Also, when I rev in park speedometer jumps up, to 30-40 MPH. I tried to recalibrate speedometer, but when I put it in gear MPH went up. Car didn’t move, but is sending VSS pulses then stops.

    Using Terminator X Max, DBW, 4L60E/4L80E harness. Setup speedometer in one of the four Holley outputs to Dakota VHX Dash. Stuff I’ve tried:
    1) I unhooked speedometer output wire to Dakota Dash, speedometer still jumps up on the Holley laptop tach screen. Revving engine in park or driving.
    2) I replaced speed sensor. No change.
    3) I changed to a different output for speedometer. No change.
    4) I pulled speed sensor out of the 4L60E, still hooked up to the Holley harness. Revved it up. Speedo zero MPH on the laptop. No VSS sent.
    Any ideas on my problem. Bad ECU? Bad harness? Somehow getting noise from the coils/tach wire/harness? Any ideas are appreciated! Thanks.

  2. #2
    Join Date
    Dec 2009


    Quote Originally Posted by RDewild View Post
    Had everything working great for a couple weeks in my ‘56 Chevy. Speedo was working perfect everything dialed in great, then this issue came up.
    I'd try doing an Ohms continuity test (while wiggling wires) on the VSS harness.
    May God's grace bless you in the Lord Jesus Christ.
    '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/3000 RPM converter, FPP aluminum driveshaft, FPP 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 MT tires.

  3. #3


    Thanks for the help! Tried these things today:
    1) I pulled the transmission harness and performed ohm test. Checked out good. Tried to wiggle the harness and ohm. All checked out good.
    2) I rerouted trans harness a different way in the car. Away from other Holley wires. No change.
    3) I pulled the VSS sender out of the transmission again. Hooked up to Holley harness, I can tap the sensor mounting bracket and see 100 MPH on the laptop . Jumps up and down. Will do this with three different speed sensors. Really weird.
    Engine was not running on the #3 test.
    Any other ideas are appreciated.

  4. #4


    Any update to this? Possibly your VSS harness got too close to the exhaust and caused some heat damage to the wiring or connector?

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