i did a 5.4 to 4.6 swap would i have too change the computer also?

The computer is set to the 5.4. not much difference except some fuel control issues. i would try it to see how it runs before getting a new computer.

Roy

i already place the engine in and its runs good but it has a stall to it and it smokes real bad and i was wondering would that computer make it smoke

if it is giving a rich command, yes. the 5.4 requires different fuel settings and that may be making it run rich or it may be an issue from the other motor as well.

get a shop to monitor the computer trims and tell you what is happening

Roy

can i use the computer out of the car that the motor came out of instead of going thru trying too drive it too a shop

no, the vin is burned into the computer and if you use that one, it most likely will not run from a vin mis match. you may be able to have the current one flashed by the dealer. call a dealer service department and see what they say

Roy

i spoke with a mechanic at the ford dealership and he said he couldnt flash the computer over to a 4.6, he told me too just get a 4.6 computer to put in there, how do that sound?

not right if he means a used one. the computers are the same, they just need different information

Roy

well i did get a 4.6 computer and the truck started up and shut off and when i try too start it up it wont stay running

i have installed a computer and a mustang before and it done the samething and when i went back too it the next day it ran perfect do you think i need too give it time to reprogram?

it does not reprogram itself. they have to be flashed.

it sounds like a security issue. did yours or the donor have a security light??

Roy

yes it does have a security light

that alone will stop it from starting. it would have to be programmed at ford to release the security lock

Roy

Ok could I have the 5.4 computer that came with the expedition flash the the motor that I put in

it goes by vin number and yours will show the 5.4. you need to speak to the dealer about this. they may be able to enter the code for the 4.6 if it was available for your truck. yes, the 4.6 was an option. give it a try

Roy