no acceleration after starting to drive

[stephenmc]

hope someone can help. I have two mechanics baffled. 2002 5.9 with 532K. engine starts perfectly and will recognize pressing accelerator while in park. Once I start moving the engine bogs down. Goes through several gears but will not get over 30-40 mph. this is with petal to the floor. After about a mile if I completely stop and start moving again it takes off like a bat out hell, normal. Only does this while sitting overnight and now its doing it after sitting in sunny spot all day. batteries are 6 months old and grounded well. new lift pump and injector pump installed 7 months ago. new TPS I installed myself 2 months ago when it stared doing this and I thought that was the problem. I'm not a mechanic but mine was closed for two weeks so I took on that task. injector pump was taken off and tested on some 300K machine and performed perfectly. reinstalled, problem still exist. HELP!

 

[kevkev]

Torque converter?

 

[matt.ferguson439]

Does it sound like the fan is going overtime when it's bogging down? Mine did that until I changed the fan clutch. The replacement still isn't great, but it's a cheap part. Still not nearly as bad as it was though.

 

[Recoil]

Do you have any codes?