OBD1 Swap... what do I need?

[John1180]

I have a '98 s52 with a horribly hacked off wiring harness( and everything else thanks to the fools who took it out). I also just got the intake manifold, red 413 ecu, and complete wiring harness from a 94 325 M50 with an automatic trans. Can I use this for a swap? What do I keep from the S52 and from the M50? Which thottle body do I use? Is the automatic wiring harness usable?

[BeirBrennerE30]

yes you can use the auto m50 wiring harness as long as it has the connectors for the knock sensors and the Vanos. however you will probably want to remove a large amount of the unneeded wiring from it.

for a full obd1 swap you need...

OBD1 harness of some kind
OBD1 DME (413 or 506) 506 is the only m-specific dme
OBD1 intake mani with TB(not 100% necessary but nice to have)
OBD1 crank sensor(with the bracket to hold the wiring away from the acc belt)
OBD1 cam sensor
x2OBD1 knock sensors
OBD1 AIT sensor
OBD1 HMF
OBD1 Coolant temp sensor
OBD1 o2 sensor
OBD1 vanos solinoid or buy the pigtail extension for the obd2 unit
OBD1 exhaust manifolds or weld up the egr passages on the obd2's
e30 Temp gauge sensor mounted in a manifold or drilled into the head
You need to modify the bracket that holds all this wiring to the block
figure out what to do with your PCV
modify the valve cover to fit the coil wiring

i think that is everything.. maybe forgetting something

[rThor432]

^^ Sounds right to me. I cant remember anything else. Well, I guess the coil pack harness.

[John1180]

There are two temp sensors on the M50, which one do I need? Which IVAC motor is used the s52 or the M50?

[Farbin Kaiber]

At least it went into the right subforum, I'm surprised no one said use the .

[whysimon]

OBD1 crank sensor(with the bracket to hold the wiring away from the acc belt)
OBD1 cam sensor
x2OBD1 knock sensors

So these are the sensors I'm going to need?

[BeirBrennerE30]

OBD1 crank sensor(with the bracket to hold the wiring away from the acc belt)
OBD1 cam sensor
x2OBD1 knock sensors

So these are the sensors I'm going to need?

so did you actually read the post??? you need all of those sensors... not just a few... all of them

[Jean]

^ x2.

coilpack harness on obd2 engine is seperate... and you can also swap the valve cover to obd1 along with coil packs.

[rThor432]

coilpack harness on obd2 engine is seperate... and you can also swap the valve cover to obd1 along with coil packs.

Good point. I couldnt remember for sure if OBD1 was separate or not. I've got the OBD1 harness with the OBD2 valve cover and coil packs. I just like the plastic cover because it is lighter.. (I'm big on saving weight up front.)

[CorvallisBMW]

http://www.r3vlimited.com/board/showthread.php?t=115570

[matt]

Good point. I couldnt remember for sure if OBD1 was separate or not. I've got the OBD1 harness with the OBD2 valve cover and coil packs. I just like the plastic cover because it is lighter.. (I'm big on saving weight up front.)

Easier to put oil in, as well. I really prefer the plastic one. They are not terribly expensive new, either.