intermittent no start, codes fixed no codes now st

[turbopowered68]

Long story short version yesterday no start condition code for crank position sensor, O2 sensor and knock sensor. Today I replaced the Crank Position and O2 sensors the truck started right up. I even started it a few times and all good.
I finally let it idle so that it can cycle the fans but that never happened the truck hit 197* and never went any higher and the fans never came on. Then after a few minutes it shut off and now back to a no start condition. Also when it first shut down the info display read "reduced power" help please

 

[Rocket Man]

What are the current codes?

 

[OR VietVet]

It would also help to know if any CEL was on before the no start problem. Was it a no crank problem or a crank and no start? Like Mark said, any codes now? What year? I would be very surprised that the O2 sensors and knock sensor codes caused a no start condition. Any recent work before the problem started? Details would be nice.

 

[rockola1971]

It would also help to know if any CEL was on before the no start problem. Was it a no crank problem or a crank and no start? Like Mark said, any codes now? What year? I would be very surprised that the O2 sensors and knock sensor codes caused a no start condition. Any recent work before the problem started? Details would be nice.

02 sensors are ignored until pcm goes into close loop mode. TPS, TAC module, Throttle pot and all associated wiring could cause this problem. Most likely its the TPS or its wiring harness. The wires typically break a few inches away from the plug at the TPS. The wires will break but the insulation wont so you cant visually see the break but you can feel it when running fingers over each wires length. A TPS with a worn spot can mimic this symptom too. The plug with wiring harness can be bought on rockauto and is easily spliced in to replace the old.

 

[turbopowered68]

ECM connection corrosion is the culprit. need to replace it and the ECM