Hal,

I have had the same problem. I have one of the initial batch of 44 autostarts (before they discontinued them and switched to the Gold).

In my Savex L-39, I have probably put twice as much fuel through it on the ground as I have in the air, trying to stop it flaming out on acceleration. As I got it from Wren, the acceleration delay was set at around 15-20. It would flame out at about 120k. Pushing the accel delay up to about 30 initially cured it, but after a couple of flights on the same day the problem returned. Upping the delay to 45 seemded to stop it flaming out. Returning to fly the next day it would again flame out on accel with the same settings that worked the previous day. I eventually had to set the delay to 60, but then started to see some other major problems, such as not being able to reach full power, erratic throttle response and one case of it not dropping below about 90k even with idle set. I spen about 10-15 starts that day trying to troubleshoot it.

Talking to Sarah and the team I sent it all back and they found that some of the fuel nozzles were blocked and that the NGV was cracked (probably the result of a hung start due to a failing battery). $300 of repairs later and with some of the new Gold parts installed and a FOD screen added it should be back in my hands any day now, supposedly putting out more thrust than before. It's now a hybrid configuration, not the full Gold spec. I also have had Wren replace the NiMh battery with a LiPo as after only a couple of hours the 650mAh battery had lost almost half of its capacity and could hardly support 2 starts and a run.

According to Wren the acceleration delay setting is not very sensitive with the bigger numbers, and changes in ambient temperature can significantly effect the required settings.

Good Luck

Paul