I also have a Ram500 my engine gave me problems to. I had replced the starter motor with speed 300, I also had to replace the fuel pump. My engine would throw flame around 70-80k rpms. The fuel pump seemed to stall then speed or maybe the gear was slipping. I once removed all the electronics from the eng and submerged the eng in degressor 409 cleaner. Back flushed the fuel line, blow air though the eng. Reinstalled electronics and lube the bearings. When I started the eng my full speed PWM was 525 at 150k. Finally the best for last, I replaced the ram fuel pump again same problem this time I used a AMT Mercury pump. First I adjusted My start PWM to 75-80 next I adjust my propane to 50. I also switch to propane not powermax. My eng starts smoother and my full power PWM is 325 at 150k. My idle to full power takes 3-4sec .