E30 engine swap wont start!

[BenEvans 0]

hey all,

i am in the proses of swapping my 1990 320i's engine for a m20b25 along with swapping the auto for a manual.

the new engine is in and all the components are in. the engine is a p/f block with all motronic 1.3 gear on it. i went to start it for the first time yesterday and got nothing when the key was turned.

after learning a trick (screwdriver over the starter terminals) i managed to get it going. i then turned the key off and the engine turned off. but the engine will not start using the key.

the voltmeter reads all the correct voltage across the starter motor and ive checkd the ignition switch witch is fine.

if anyone has any idea as to why i cant turn the car on with the key please let me know!

Cheers

[323e30 0]

you need to wire it up so the car thinks its in nuetral

or remove the relay that controls this. Its generally easy but hard to explain without it in front of me but the relay is located under glove box. You will see a thick yellow and black wire going to it. The yellow and black wire will have a plug. On the other end of the relay is another wire same thickness. (may be same color but cant rember) it will also have a plug on it and it should fit the plug on the yellow and black wire.

This wire is to start your car. As being an ex auto it needs to be in park to start.

[323e30 0]

you could just be lazy and twist the wire together that would normally go to the shifter.

[BenEvans 0]

cheers.

i went and tried to see what u ment but couldent.

i saw a tick black and yellow wire but couldent see where it went.

not wanting to be lazy, but just to check to see if it works which two wires do i twist togeather?

[323e30 0]

umm, cant remember of the top of my head. but get your shifter out (the one you removed) get a light bulb and a battery.

The two wires that make the light bulb turn on in Park or Neutral are the wires you want to drive. (think its green brown stripe and black brown stripe) but any how test all of them untill you have a pair that do this. they should only work in these positions. No others.

You dont need the shifter in the car to test this so miss matching wires will not effect anything so its safe.

hope im making sense haha im an electrician by trade so I can get a bit carried away sometimes :s

[Nobimmer 694]

I had the exact same thing. Turned out to be exactly what Mike said.

Listen to him. He's a genius.

[Andre3000 55]

how does the engine run anyway?

[BenEvans 0]

cheers guys! well mike...

that was the problem and now thats sorted all thats left to do is fix the clutch and stop the engine from sounding like a tractor! i dont think its fireing on all 6 cylinders so i have a mobile mechanic coming to tell me what needs to be done.

anyway cheers again mike, much appreciated.

Ben

[jochen 4]

that was the problem and now thats sorted all thats left to do is fix the clutch and stop the engine from sounding like a tractor!

Got any oil in it ...??

[BenEvans 0]

haha yea i do.

cheers

[rds 0]

you could just be lazy and twist the wire together that would normally go to the shifter.

Haha, thats the way! works a charm