OBD 2 Cord ?

[3yearplan]

I am using the drivetrain out of a 2004 Mach 1 and I am only using the factory ecu. Do I need the OBD 2 cord to make it function? It is the cord that is under the dash of the Mustang to plug into for trouble codes etc. Any help with this would be appreciated.

Thanks, Mike.

[dforthof]

Yes, if you ever need to pull DTC's then you'll need the OBD-II cable. Keep it, you'll regret not including it.

[3yearplan]

That was my thought process also, but I don't actually have the cable or know where it plugs into the harness. :confused:

[acth4347]

What harnesses are you using with your 2004? I believe the engine/ECU harness is one harness and the cluster harness connects to it. Usually the OBD-II is part of the cluster harness. Check out this link on the other forum for some info on 2004 and cluster.
http://www.ffcars.com/forums/45-ford-modular-engine-roadster-builds/241267-wire-harness-help.html

[3yearplan]

I'm using the factory engine harness. I have "A" cluster harness out of the same year Mustang, but I'm fairly certain that OBD II cord was not present. I'm assuming I'll have to diet out the cluster harness to only include the OBD II cord/connection since I am not using any other part of that harness. Thanks for the reply and the link.

Mike

[CraigS]

Based on Lexus experience (which I think is applicable since all this obd2 stuff is a Federal regulation that applies to all cars) you 'may' be able to get away w/o that obd2 harness. Current cars sense whether that connector is there or not, I just don't know what year Ford may have adopted that. But I would make an effort to have the obd2 connector installed. It will be a ton easier to do it now and the probability that you will want/need to pull codes is quite high. There are a lot of other car systems that feed info into, or take info from the efi ecu, so when those systems are not connected it is not at all certain whether the ecu will pop a code or not.

[3yearplan]

I agree Craig, I definitely want the cord/port to be able to read trouble codes. I will have the computer flashed to delete PATS, the after cat O2 sensors and may go with a different tune as well based on a few other things and hopefully this will end up being a stand alone computer strictly for engine management and not necessitating other tie ins to make everything happy.

[dforthof]

Do the OBD-II cord now, it would be a pain after the car is done. Just buy an OBD-II recpetacle here: http://www.aldlcable.com/products/obd2connv.asp make sure you buy a bunch of extra pins with it. Then use the items I've attached from the 2004 Mustang Service Manual to pin the connector to the correct pins on the PCM, also be sure to run a power and ground to the OBD-II connector as well. I believe I've included eveything you need, but just ask me if I missed something.

[3yearplan]

Thanks for that link, really appreciate it, everything else came through as well. Very cheap route to go.

Thanks again, Mike.