Help needed. M42 e36 into e30 316i.

Wed Apr 05, 2017 5:04 pm

Hi guys.

I have recently dropped my m42(e36) into my e30 after swapping the sump and exhaust manifold.

Now I need to tackle electrics, I have a rough idea where to start but I really need someone to point me in the right direction that has done this before.

I've searched many forums but nobody has got a whole thread on it!
I am using the e36 harness.

So far I have cut off the e36 plug and I've got my original off of the old 316i loom.

Any help would be really appreciated.
Thank you

Wed Apr 05, 2017 6:34 pm

For the most part, just join identical coloured wires together.
Do that, and tell us what you have left over.

Wed Apr 05, 2017 8:59 pm

That's my plan at the moment !

, thank you for getting back to me and I will be sure to upload!

Wed Apr 05, 2017 11:24 pm

One other thing to check. What colour wire is connected to pin 20 on the car side of your C101? If the C101 engine loom plug you are using is the one that was originally fitted to your car, the colour of the wire, if any, on pin 20 will do instead.

Thu Apr 06, 2017 4:12 am

I hope its ok to post a link to another forum. Here is my thread from a forum in NZ. This should help you out. http://bimmersport.co.nz/topic/57079-e30-m42-swap/

Thu Apr 06, 2017 5:36 am

I used the later E36 M44 engine and the wiring was the same as doing an M52 conversion - the M52 wiring charts are in the wiki. I can't see the E36 M42 being much different.

Wed Aug 16, 2017 8:42 am

can you not just use the m40 / m42 loom for m44 conversions??

Wed Aug 16, 2017 11:28 am

Quaser wrote:can you not just use the m40 / m42 loom for m44 conversions??

The M40 loom won't work. You can use an E30 M42 loom but you need to swap to everything M42 (loom, inlet, ECU etc etc) from an E30.

For what it's worth, I used everything M44 and it makes for a great car. The conversion (including wiring) is pretty easy and the M44 has better torque lower down so it makes a really good daily driver.

Sun Sep 10, 2017 10:17 am

Hi all I'm in the middle of doing this conversion to my touring Iv wired it up as has been said. I have no fuel or spark. If I use a wire across the relay I get fuel but obviously no spark. I'm going to try another ecu this morning see if that helps. If not I'm stuck. Iv fitted an m42 from an early e36 318 because I read they were pre ews but I almost feels like an immobiliser fault it cranks over as it should