Hello all, I have a 1997 XD with 170,000 miles. Starts right up, idles great and runs great, UNTIL the engine gets good and warm. This takes approx. 10 minutes, that's when the engines starts to run rough and won't rev past 3,000 rpm and steadily declines UNTIL it won't rev past 1500 rpm. Still idles fine, will start and restart fine, but backfires inside the intake, and at the exhaust. Let the engine cool down, everything is good UNTIL it warms up.
No engine codes being thrown

I've got 30 psi fuel pressure at the rail at idle and the regulator goes to 38-40 psi when revving up, (until it sputters then regulator jumps up and down with the engine).
New auto lite plugs and 8 mm wires within the last 20 miles.
new fuel filter at the same time.
I've taken the fuel pump out twice and examined it and checked for debris, first time seemed to help things a bit, until I let the rover set for 3 months (dead battery).
sea foamed the intake less than 100 miles ago, and stuck some in the tank.
Rover has been fairly well taken care of.
Ideas? Thoughts? Fuel temperature sensor?
thanks a bunch!