Having a very vexing problem with TSIO-550 engine – from Performance Engines.  Plane hasn’t flown yet and we’re struggling to correct that deficiency.  Major hurdle is the engine.

Has one EFI (plasma III) and one mag.

Ran fine up until about 2+ months ago when we decided to send the control box back to Klaus to upgrade it to current mods – Supposedly this would make it more durable especially heat resistant and maybe some other improvements as well.  We have it inside the cockpit so heat was not a major issue, but we just thought it would be better to have the newest modifications. 

After reinstall engine runs VERY rough on EFI.  Checked phase and that was ok but we discovered that one coil would not produce much spark in static tests.  We proved that the problem emanated from the control box by moving the wires at the coils and having the problem follow the wires.  Next changed wires at the box connection to ascertain that wires were OK.  They were.

Removed box and sent back to Klaus.  He said that something was wrong with the wave forms and would repair.  I think he sent us a replacement box a few weeks ago.  Will try to confirm whether he reworked the control box or replaced it.  We installed – retested the phase settings and verified stronger appearing spark across the coils.  So far so good.

However the engine still runs ragged on the EFI and runs somewhat uneven on Mag/EFI combination.  Runs same on Mag only.  Have pulled plugs and found one or two  EFI plugs wet – (not firing?).  I’m not sure which plugs those were.

Strangest finding is that I tried changing the B and C phase wires at the control box to see if maybe we were off in the phase settings.  Ran a lot worse as expected but the weird thing is that when I turned off the EFI to run on Mag only, the engine ran  very rough.  Putting the wires back in the correct order on the control box returned the conditions to OK on the mag – uneven on both and very ragged on EFI.

Any suggestions?

Regards,

John Barrett, CEO

Leading Edge Composites

PO Box 428

Port Hadlock, WA 98339

www.carbinge.com