I have a Yale GLP25TKE with a stalling issue. It has the Mazda FE engine with the Aisam regulator and the idle injector setup.

Unit keeps stalling when it gets hot, one thing I've noticed is when you give it full throttle it runs ok but as soon as you release throttle it just about dies. Doesn't appear to be any adjustments on the regulator or mixer. I have another machine identical on site, I've swapped the two kickoff solenoids, the injector, and filter, the power diaphragm, the ignition coil, cap and leads, drained out the tar in the regulator. I also disconnected the 0xygen sensor and it made no difference to the idle which I thought was strange because according to the book I have, once the engine is warm the gas system goes into closed loop mode which runs off the oxygen sensor. Next step is gonna be swapping the whole regulator out.

Any other ideas? Thanks