Grand Marquis and p71 engine swap

[Crown Vicman]

Hello how are yall doing, good I hope. I helped a friend put an 06 grand Marquis motor in a 03 p71. The motor only has 80,000 miles on it. I have know idea whats going on but the car runs rough and smokes bad like its getting too much gas. The car idles too high as well. Not sure if his throttle body is bad or maybe he needs the computer from the 06. We had to swapp over his throttle body because the newer cars are electronically controlled. Any help will be greatly appreciated.

[tobiasg1995]

Did you swap the pcm also?

2006 GMQ, 2010 CVPI

[RubberCtyRauder]

06 is drive by wire, the other is throttle cable. it needs the 06 pcm. no more cop chip

[Bondfreak13]

Reuse the 2003 Throttle body.

[Crown Vicman]

no we had to change the wiring harness

[Crown Vicman]

Reuse the 2003 Throttle body.
yes we did reuse the 03 throttle body and we had to use the 03 fuel rail

[larryo340]

Engine light on?

[tobiasg1995]

But which pcm did you use?

2006 GMQ, 2010 CVPI

[Crown Vicman]

engine light is on and we kept the 03 pcm just changed wiring harness because sockets were different

[Crown Vicman]

But which pcm did you use?

2006 GMQ, 2010 CVPI
and its an 2003 crown vic p71

[tobiasg1995]

What codes are showing?

2006 GMQ, 2010 CVPI

[Bondfreak13]

Why Did you swap the wiring harness? Why couldn't you just reuse the 03 stuff? I know you said the "sockets" were different. which parts?

Something I learned years back when it came to engine swaps. Anything Mechanical goes to the new car, anything electrical stays with the old car.

from the 06 you should have used the following, basic long block, intake. Then you reuse the 03 fuel rails, injectors, plenum and throttle body, egr, TPS, and other related sensors.
Though some of the electronics may have changed, as far as I know mechanically the 4.6 didn't.

[larryo340]

^^^^ +1 on everything posted above

With that said you may have a stuck open injector. You should read the codes.

[Spectragod]

Why Did you swap the wiring harness? Why couldn't you just reuse the 03 stuff? I know you said the "sockets" were different. which parts?

Something I learned years back when it came to engine swaps. Anything Mechanical goes to the new car, anything electrical stays with the old car.

from the 06 you should have used the following, basic long block, intake. Then you reuse the 03 fuel rails, injectors, plenum and throttle body, egr, TPS, and other related sensors.
Though some of the electronics may have changed, as far as I know mechanically the 4.6 didn't.

^^^this^^^!!!!

[Crown Vicman]

Found out an injector plug wasn't pushed all the way in and that we were losing vaccuum. The car is running great now. I would like to say Thanks guys and I really appreciate all of your input.