New Member, 97-3.8, Swap...help?

[Tatrabbit]

97 3.8 bad motor. Have 2001 low mileage 3.8 to put in it. I have been told numerous things, it's plug and play, have to use 97 wiring harness, just have to change cam sensor, have to use 97 fuel rails and wiring harness, and that I would have to use entire 97 top end and wiring harness..... so now I'm just confused.

 

[Davedacarpainter]

Welcome to Stangnet.

I dig the confusion thing, lots of views that conflict with each other make it a bit of a pita.

I’ll move your thread to the tech forum in the ‘96-‘04 subforum. You should get some sound advice there.

It’s good to have you with us.

 

[wmburns]

Let's see if we can clear some things up for you.

Yes you will need to reuse the original wiring harness. As far as the PCM is concerned the new motor needs to "appear" the same as the old motor electrically.

In the same vein the 1998 and older does use a different cam sensor than the 1999+. So because the motor needs to look the same (electrically) then the same style cam sensor (2 wire vs 3 wire) needs to be used.

The other difference is that after 2000.5 Ford switched to internally balanced V6's. Before that they were externally balanced. It's important to NOT switch balance parts between the different motor types.

Regarding the fuel system. A 1998 and older Mustang uses a return based fuel system. Where as a 1999+ uses a return-less system with a Fuel pump driver module (FPDM) to control the fuel pump. Since we need the motor to appear the same to the PCM that means the original fuel delivery method will need to be re-used.

 

[Tatrabbit]

Ok. So if I understand correctly I need to use the original wiring harness, fuel rails, and cam sensor. I can just switch them all over to the new motor?

 

[Tatrabbit]

Let's see if we can clear some things up for you.

Yes you will need to reuse the original wiring harness. As far as the PCM is concerned the new motor needs to "appear" the same as the old motor electrically.

In the same vein the 1998 and older does use a different cam sensor than the 1999+. So because the motor needs to look the same (electrically) then the same style cam sensor (2 wire vs 3 wire) needs to be used.

The other difference is that after 2000.5 Ford switched to internally balanced V6's. Before that they were externally balanced. It's important to NOT switch balance parts between the different motor types.

Regarding the fuel system. A 1998 and older Mustang uses a return based fuel system. Where as a 1999+ uses a return-less system with a Fuel pump driver module (FPDM) to control the fuel pump. Since we need the motor to appear the same to the PCM that means the original fuel delivery method will need to be re-used.[/QUOTE


Ok, makes sense. So if I am thinking this through correctly, I will need to change the intake? The intake and everything above it is completely different, no fuel rails on the 01..... and what about the trans? The 01 came with the trans still bolted in place. I haven't checked to see if 97 harness will match 01 trans. Both the 01 and 97 trans are good, both automatic .

 

[Tatrabbit]

Let's see if we can clear some things up for you.

Yes you will need to reuse the original wiring harness. As far as the PCM is concerned the new motor needs to "appear" the same as the old motor electrically.

In the same vein the 1998 and older does use a different cam sensor than the 1999+. So because the motor needs to look the same (electrically) then the same style cam sensor (2 wire vs 3 wire) needs to be used.

The other difference is that after 2000.5 Ford switched to internally balanced V6's. Before that they were externally balanced. It's important to NOT switch balance parts between the different motor types.

Regarding the fuel system. A 1998 and older Mustang uses a return based fuel system. Where as a 1999+ uses a return-less system with a Fuel pump driver module (FPDM) to control the fuel pump. Since we need the motor to appear the same to the PCM that means the original fuel delivery method will need to be re-used.[/QUOTE


Ok, makes sense. So if I am thinking this through correctly, I will need to change the intake? The intake and everything above it is completely different, no fuel rails on the 01..... and what about the trans? The 01 came with the trans still bolted in place. I haven't checked to see if 97 harness will match 01 trans. Both the 01 and 97 trans are good, both automatic .