Sharky, thanks for your reply.....let me update you ... butI will also check the alternator stuff too!!!
Okay here goes as to what I think happened
....out of the blue......we got it started at 10.30pm last night......why.....we're not sure!
We did go back and check the resistance on the CPS and the spare CPS that we tried to start the engine with.....both about 540 ohms which depressed me no end as I think thats about spot on? But through reading lots of good threads online….our symptoms would have been caused by the CPS sensor not working, either a dodgy lead or some dirt etc…...
We double checked the 12v to the main relay and to the FP relay....all good.....good continuity to the FP wires to the fuse box and to the pump. Linking the main and fuel relay forced the in-tank pump to run but nothing at the main pump (which I think is important - now). I was looking for a confirmed 12V to the fuel pump under the car, but it turns out, this will only see 12v when the demand for the pump to run is present…..with no leaks and the hoses in place, the pump will prime and then stop and voltage disappears…..so that probably was a red herring in terms of me thinking the fuel pump wasn't get a demand all along….I think it was and we only had a no spark issue? There is a chance the fuel pump is still sticking at times ( I think that was the issue when we put it on the trailer going to MSR - but my other theory is the old breather that came from the charcoal canister (now gone) was closed off (me) and may have created a vacuum in the tank and air locked the pump…..but again, I don't know how well we diagnosed the no fuel, no spark issue…..
We changed ECU's for the one we took apart and ran a wire to monitor voltage on pin 37 (I guess we read somewhere that this pin should have 12v and it did)?
We had no spark at #1 plug for 2 days...... also checked the king lead for spark and same thing.
NOTE: Our wipers stopped working ages ago, so we hard wired them in to a new switch in the car......they had also stopped working recently??? I removed the large black relay in the fuse box a while ago as they ran without it anyway.....I can't remember if this was ages ago as in before it stopped working or closer to when it first failed to start…..I think I took it out during the engine install and we were having all the issues with wires melting etc……and it did start despite that!
Now, I am not sure at what point but we had almost all the wiring laid out, we changed back to the original CPS that used to work on the car and we had been messing around with the OCM relay, the connectors for the pulse #6 lead and the CPS (any idea why those 2 are interchangeable)??? Oh, and I put the wiper relay back in again and the wipers worked?
We tried the engine and we got spark at king lead, but not at #1 plug? Changed the distributer cap and leads over and she fired up! For laughs we put the old dist cap and leads back on....and it still worked? Changed the pulse sensor #6 and CPS connections over and it didn't work.....
Took the wiper relay out and it still works.........
So - Yayyyy its working again......but I am not at all sure if we mended it, or there is something lurking in there that will do this again and spoil a race day perhaps???
I'd still like to remove all remaining bunches of wires from the car and end up with the bare minimum in there......not weight saving just ease of use and removing all the crap that could cause this!
We don't have the OBC plugged in anymore with no ill effects to date......
I think I am learning more about this E30 but man its been a round about route to an unclear solution!!!