Hi everyone well got the truck going had to redo the timing , but now when I put it in drive and push on the gas it will go real slow and slowly build up speed , I can put my foot all the way to the floor and it will take its own sweet time to get up tp speed , but in park in you push the gas peddle to the floor it revs right up , any ideas ? Thanks if anyone can help

 

Forgot to let you all know its a 3.0 3rd generation

 

clogged cat? remove the upstream oxy sensor(if it has one) and if it seems to run better then it's probably a cat.

 

Don't you mean the downstream sensor? The one behind the cat? That I believe is called "the downstream" sensor. The upstream is before the cat. Right?

 

It's the upstream....IF the 3.0's even have an upstream one. It's a little trick that if the converter is clogged then by removing the upstream sensor the hot air can escape thru the small hole and the engine seems to have more power.

 

If the autotrans is shifting 1-3 correctly then the possibilities below
Else trans stuck in second gear.

Possibilities.
TPS is bad, Not registering throttle up other then not idle.
On sticks you rev first so its less noticeable until higher altitudes then it its real sluggish.
The engine runs off the AFM only.
I have had 3 of them go bad like this and no code.
This also causes jerkiness in stickshifts.