For the last two years my truck has haunted me. It runs with about 90 % power. If I floor it, it slows down. When i'm cruising any speed its seems when I go up hill it will shut down to about 10% power. for two years. I have changed plugs, wires, coil, maf sensor, egr valve, throttle air mixture sensor, throttle position sensor. About a week ago it started this. You start it and it runs for about 10-30 seconds if you turn the key again, nothing. If you turn the key off and then start it runs for 10-30 seconds. When it stalls it stumbles. if you spray starting fluid in the throttle body it will run as long as you keep spraying. It has between 40-50 psi fuel pressure constant never drops, no intake leaks.
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Thanks for all your help everybody. I fixed it