HELP!! v6 to v8 swap

[99L#411]

I have a 98 v6 5 speed and we just installed a 98 4.6 with an auto and PI heads from a 98 GT convertible. I swapped the computer out and the motor and tranny are in and ready to be started.

I work for a local lockshop and have the PATS programmer.I had a blank PATS key cut to fit my ignition and had it programmed to correspond with the 98 GT computer. But after all the programming was done, the THEFT light still flashed. We tried to completely dump the system and start all over but the PATS programmer said that it could not instablish a connection to the computer.

IS the dash harness for a 98 v6 different from a 98 GT? Please help me anyway possible.

 

[vteckiller2000]

Did you change the engine harness and the firewall/computer harness? There are 2 harnesses that you will need to change one is the one the computer connects to and runs down the passenger side front frame rail and also connects to the engine harness with that big ol honkin square connector on the pass side firewall. The other is the engine harness. You will also need to change the instrument cluster. If you are still running the v6 firewall/computer harness nothing will work and it won't fire.

 

[99L#411]

Did you change the engine harness and the firewall/computer harness? There are 2 harnesses that you will need to change one is the one the computer connects to and runs down the passenger side front frame rail and also connects to the engine harness with that big ol honkin square connector on the pass side firewall. The other is the engine harness. You will also need to change the instrument cluster. If you are still running the v6 firewall/computer harness nothing will work and it won't fire.

The engine harness is in as well as the computer harnes and the instrument cluster. Do you know if the dash harness is different?

 

[vteckiller2000]

The engine harness is in as well as the computer harnes and the instrument cluster. Do you know if the dash harness is different?

The dash harness is the same. Did you change the CCRM relay box in the pass side fenderwell?

 

[99L#411]

The dash harness is the same. Did you change the CCRM relay box in the pass side fenderwell?

my v6 did not have 1. but when i put the v8 harness in, i put a brand new relay in it.

 

[vteckiller2000]

my v6 did not have 1. but when i put the v8 harness in, i put a brand new relay in it.

I'm assuming that the computer is for the same year as the chassis and for an automatic, and the v8 harnesses are for the same year car v8 car as the chassis is. Is this correct? The v6 harness should have had a CCRM in the front passenger fenderwell as well. It is large and mounted on the inside of the frame, you can only get to it with the fender or wheel well liner removed.

 

[99L#411]

oh ok. yeah i have that. i thought you were talking about a small relay that was on the v8 harness, but not on the v6.

 

[vteckiller2000]

Did you change it to the v8 one? They are massively different on the inside and nothing will work if you use the v6 one.

 

[Sublimize23]

FWIW, you can disable PATS with a computer tune, if you ask for it.

 

[vteckiller2000]

FWIW, you can disable PATS with a computer tune, if you ask for it.

I don't think it is the PATS that is giving them trouble. I think that the car might have to go to the dealer to purge the system though. IIRC the ford dealer here had trouble setting up the PATS on mine and finally had to just purge the entire thing, something with the cluster not matching the PCM and they needed to make it learn the new cluster since the cluster is keyed for the PATS system also.

 

[03cobramanIII]

the pats system sucks .
i did need to know whats all needs to be done , cuase i want to do the same on my wifes car, its a 99 v6 auto, and want to go 99/04 4.6 auto? will the same trans work , i know the k memeber is different. and got one , but dont know about the fuelpumps and wiring and what ecm to use? i'll post a post later good luck man !

 

[vteckiller2000]

the pats system sucks .
i did need to know whats all needs to be done , cuase i want to do the same on my wifes car, its a 99 v6 auto, and want to go 99/04 4.6 auto? will the same trans work , i know the k memeber is different. and got one , but dont know about the fuelpumps and wiring and what ecm to use? i'll post a post later good luck man !

The K member and fuel pump are the same, you dont need new ones. The trans is the same also. You need the ECM firewall harness and the engine harness. Use a 99+ GT auto ECM.

 

[ctothap]

The K member and fuel pump are the same, you dont need new ones. The trans is the same also. You need the ECM firewall harness and the engine harness. Use a 99+ GT auto ECM.

damn, is sound like you know your shit, i might have a few questions for you, im getting ready to do a 98 cobra swap into a 99 v6.:beer: