M20 Swap complete, Fuel comes, Engine turns but no SPARK !!

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Post Fri May 02, 2014 12:48 am

318i m40 to 325 m20

Image

So we finally got the running gear in

loom connected
engine earth connected
all wires metal brushed
two good ECUs tried
fuel comes

you turn the key, engine turns but no spark
:cry: :cry: :cry:

engine came without loom or crank positioning sensor.

used both from touring abs facelift 325

can it the cps not working with this engine?

have we missed anything ?

Thanks in Advance
e30topless
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Post Fri May 02, 2014 12:59 am

try swapping over the plugs from the CPS and the Pulse lead, they are the only 2 plugs on an M20 than can be mixed up
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Post Fri May 02, 2014 1:01 am

e30topless wrote:try swapping over the plugs from the CPS and the Pulse lead, they are the only 2 plugs on an M20 than can be mixed up
Tried this evening, no dice

whats next to try ? :roll: :roll: :roll:
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Post Fri May 02, 2014 1:08 am

you got any pics ?
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Post Fri May 02, 2014 1:12 am

I will take some tomorrow, anything in particular you want to see ?
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Post Fri May 02, 2014 6:45 am

If you've got no spark, you also need to confirm that you've got no fuel when cranking. If you haven't got either, it's definitely a CPS issue or associated electrickery. If it's just spark, it's something to do with the ignition system or the green wire.

This handy link should get you up and running:

http://www.e30zone.net/e30zonewiki/inde ... oubleshoot
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Post Sat May 03, 2014 12:24 am

That trouble shooting is great, we are going to follow it tomorrow and see what happens :roll: :roll:
I know a lot about cars. I can look at a car's headlights and tell you exactly which way it's coming
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Post Sat May 03, 2014 12:31 am

if you have fuel it's possibly a faulty DME relay, IF everything is connected properly..

it's the 5 pin relay in the 3 relay cluster on the engine loom/airbox area it's usually white
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Post Sat May 03, 2014 12:43 am

e30topless wrote:if you have fuel it's possibly a faulty DME relay, IF everything is connected properly..

it's the 5 pin relay in the 3 relay cluster on the engine loom/airbox area it's usually white
You know the loom plug, being 318 circle and the 2.5 is also circle

is it plug and play or pins are different ?

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Grrrmachine
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Post Sat May 03, 2014 9:14 am

Topless, if there was fuel then the DME relay should be working, as that powers up the fuel pump relay.

I'm suspecting the green wire myself. Do the bulb-on-coil test from the troubleshooting to confirm.
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Post Sat May 03, 2014 10:53 am

E30-Addict wrote: You know the loom plug, being 318 circle and the 2.5 is also circle

is it plug and play or pins are different ?
No, pin 20 is often used for a different purpose, but in your case it must have been OK, or your OP would have been about the flames and acrid smoke coming from your wiring looms.
There are only a few possibilities that give you fuel but no spark, and the first thing to check is for power at the coil green wire, as Grrr says.
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Post Sat May 03, 2014 11:18 am

Finalllllllly

It's *************** running now

Turned out to be a cps

Getting the exhaust, rad and other bits in now

A conversion has finally finished

Will post a build thread soon :D :D :D
I know a lot about cars. I can look at a car's headlights and tell you exactly which way it's coming
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Post Sat May 03, 2014 2:10 pm

If the CPS was at fault, then you did not have a consistent fuel supply to the rail when cranking. If you give us incorrect information, we can't give you an accurate diagnosis.
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Post Mon Jul 14, 2014 6:40 pm

After working on some issues on more than 1 car .
start the engine or make it turn ,
remove one of the spark plugs and check if it has gas smell on it ,
if it does check all 6 sparks , then clean the injectors .
specially if you have bought an engine which hasn't been running for a while .

also test the coil with a screw driver to the chassis , watch where you grab that screw driver so you won't get shocked .

also happend with me , make sure you crank position sensor is working properly .
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Post Tue Jul 15, 2014 1:03 am

Thank you Habibi for the advise

It was the crank position sensor in my case but the table made by the guys on the wiki were very helpful
I know a lot about cars. I can look at a car's headlights and tell you exactly which way it's coming