M3 Motor swap almost done, Wiring Questions?
 

I almost have the swap done. Need help with some of the wiring. The M3 motor wire harness has three quick connects next to the fuse pannel under the hood. The stock Ti only has two, What does the middle of the three M3 connectors go to on the TI? Second question the M3 runs a second air pump that the Ti doesn't seem to use. Do I need to wire this in some where?

Thanks
97BlueTI
Don
dvanlengen@mchsi.com

Don't know about the wires but unless you have the air pumps connected, you will throw CELs.

The third plug may not be on you TI depending on the year. If the plug is consideribly longer than the larger two plugs, it may be go to the CAI plumbing.

I can't tell exactly where you are.

ODB II(S52/M52) or ODB I(S50/M50) or both gens

Me?
I have M52 OBD-II.
I don't have the air pumps. I had the fault codes written out of the software by NickG.

No sure but I think it's an S52. The TI is a 97 from CA. Both the other M3's I have seem to all have the second air pumps.

You can either run Active Auto's Air Pump Sim (I think it's like $150) or go the NickG Route... or you can live with the CEL, which may not be so bad considering you're probably gonna throw other codes when you get this running. As for the third wire harness near your fuse box, it just sits there, connected to nothing... I believe this originally connects to a secondary chassis harness on the M3 to control the dual-climate control stuff.

How did you do the battery routing? Or are you deleting the SAP to run the batt up front?

We are routing the battery in the back. I have put in a pump from an M3 in the stock battery location, just like the M3's. I was just checking if anyone knew what the extra connection was for before hooking up the battery.

If you relocated the battery there is no reason not to run the secondary air pump. It mounts in the space used for the battery on the ti.

One less error code...:smile:

Is the Pump an ODB II thing or do ODB I cars have it also?

just wondering as I see a couple local 325s and ODB I Ms without it.

Definitely on OBD-II M3's; not positive on the older ones. It may have been deleted (as Steve and I have done) also. Just because it's not there, doesn't mean it's not supposed to be there...

Still have an Issue with the Idle speed wiring. The TI has the Idle speed connector as part of the motor harness. The M3 the Idle speed connector is part of the harness that runs into the car under the dash. Any ideas on how to get around this problem? If I need it, where does it run to?
Thanks
Don

That doesn't sound right to me.

I don't think there were any problems with this in my swap.

I had two wiring issues:
1) Fuel pump relay (due to engine being from an M Roadster rather than an M3- M3 motor in ti eliminates this problem)
2) Axillary fan relay (definitely worth the cost; A/C works great now) Many people who swap leave the aux. fan out, which I do not agree with.

There were no other wiring issues that I was aware of during the swap.