Power Commander III usb

Discussion in 'Softail Models' started by Roulph, Nov 13, 2008.

  1. Roulph

    Roulph Member

    I ride a 2004 softail Deuce EFI with screaming eagle air filter, plugs and exhaust. I had power commander fitted to my bike 4 month ago, when fitted in Singapore it was dyno tested and mapped. The performance has been great but after two months I started getting popping and backfires on de acceleration. I spoke to the dealer in Singapore (I am in Malaysia 300 miles from the dealer) and he suggested adjusting the throttle zero settings from 0 to 10 between 1500 - 4000 rpm. Before changing the map settings which were arrived at from the dyno I wanted to check if anybody else has encountered this problem before and to find out what you would recommend. Many thanks - Roulph
  2. wildspirit97

    wildspirit97 Senior Member

    I would also check for intake or exhaust leaks, check the spark plug condition/Gap and maybe put some new spark plug wires on. before messing with a map that worked fine before.
  3. whatyardwork

    whatyardwork Banned

    What are the elevation differences from Singappore to Malasia?
  4. 2002SilverSurfer

    2002SilverSurfer Active Member


    I agree with wildspirit and in effect with whatyard as well. Normally, it will be something other than the PCIII if you had it mapped and dyno tested. Unfortunately, even the slighest change in any of the factors (intake, exhaust, or fuel) will cause a slight difference in performance. In my case, I bought and mapped a PCIII USB for my 02 Heritage and it ran great for a while. I, like you, thought that when it started running differently that the PCIII might of needed to be remapped. Unfortunately in my case, the PCIII needed to be replaced (still does) as it was apparently removed (code word for stolen) from under my seat at any one of my numerous repair trips to a multitude of HD dealerships.

    Good Luck and let us know how things turn out.
  5. Deuceman144

    Deuceman144 Member

    G'day team,

    I ride an 05 Deuce EFI (not upgraded with PC, yet) but also noticed a significant backfire and pop on deceleration starting a few months ago. Following the advice of the excellent contributors to this forum, I checked the exhaust and indeed noticed a tiny leak around the joint near the pillion footpeg. As I needed a new tyre anyway, I decided to wait until I had it fitted as the exhaust needs to be removed to fit the tyre.

    I had the job done this week, mentioning to the mech to check the exhaust seal, and sure enough; I've been on the road all weekend and the engine's never run sweeter. I'm surprised at the adverse effect insufficient back pressure had on engine performance.

  6. glider

    glider Veteran Member

    It's great to see a happy rider:D