A9L with PMS will not stay in WOT
I have a A9L computer with a PMS series II. Brand new Pro-M mass air meter calibrated to 30lb injectors. Engine is a 347. The car runs great and made good power on the dyno but I am having some sort of electrical issue maybe. At WOT the car runs out great but the ECM jumps out of WOT to PrL 7 and PrL 8. It does this at about 3500 and 5000-6000. This is not right. I am not able to make any reliable tuning adjustments.
Has anybody encountered this before?
Some things I have done:
Set base idle multiple times.
Replaced TPS with OEM Ford product.
Checked all grounds.
Grounded the PMS box to the chasis.
Thanks in advance for any input.