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Thread: Runs rough when cold - ECU still Learning.

  1. #1

    Default Runs rough when cold - ECU still Learning.

    So I've driven my truck a few times with a new Terminator installation. Starts & runs OK, drives well when warm. I haven't "opened it up" yet since it's still in Learning mode. However, on day 2, it was pretty cool outside, and I cranked it up. That went OK. But when I drove off, it sputtered & coughed and would hardly accelerate. Is this because it's still Learning? Should I try to make any adjustments or just wait for Learning to finish? Any input is appreciated. Thanks!

  2. #2
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    Quote Originally Posted by xyzrbs View Post
    But when I drove off, it sputtered & coughed and would hardly accelerate. Is this because it's still Learning? Should I try to make any adjustments or just wait for Learning to finish?
    This indicates the Coolant Temperature Enrichment % and A/F Ratio Offset Tables need to be tuned. However, these tables can only be tuned after the Base Fuel Table (Learning) is well tuned, because they're modifiers of the Base Fuel Table. When the Learn Table (Link) values stop making significant changes, the ECU is finished self-tuning.

    Determine if it's running rough due to a rich or lean condition. Watch the Data Monitor/handheld.
    This is usually caused by a Base Fuel Table that's too lean (especially with a manual transmission).
    Manual transmission applications are better off selecting the next larger base calibration.

    You may also need to do some Acceleration Enrichment tuning.
    The AE vs TPS Rate of Change is very rich in the base calibrations.
    Again, this can only be tuned after the Base Fuel Table (Learning) is well tuned.

    Conversely, if you have a momentary lean spike, on light throttle acceleration,
    check your AE vs TPS/MAP RoC Blanking values (in Fuel Modifiers/Fuel Control):
    If they're 15 & 7, those are the old values from the V1 firmware.
    Change the AE vs TPS RoC Blanking value to 4-6.
    Change the AE vs MAP RoC Blanking value to 5-7.
    Some users reported the need for an even lower TPS RoC Blanking value.

    http://forums.holley.com/showthread....8687#post48687 (Initial Checks & Adjustments - Read This!)
    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/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

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    OK, found a blooper in my configuration. Somehow, mysteriously, my initial timing synchronization was off by about 10° (retarded). I really don't know how I ended up with that discrepancy. Nonetheless, after resyncing, she runs like a champ, even when cold. Thanks again! I still plan to research the areas you mentioned for possible tuning opportunities.
    Last edited by xyzrbs; 02-15-2015 at 08:09 AM.

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