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You'll need the loom from somewhere else but you are welcome to the ecu in return for beer vouchers. I have one of the older ecu's as well but clearly no use now!

I think I have one of those zone chip ECU's somewhere!

Got all my Motronic 1.3 stuff.

Big thanks to DrJim for sorting me out with the ECU, very much appreciated.



The plan is to do my loom tonight, then do the swap on Saturday. If time is kind to me, I might be able to re-attempt starting it on Saturday afternoon.

mate you are insane

Good luck mate. As u know give ne a call if you need vague ideas

Another attempted start today, but no joy.

Motronic 1.3 swap is complete and I believe to be correct.

We identified that the fuel pump relay is knackered, once the relay is bridged the fuel pump can be clearly heard, so a new relay is needed.

Possibly the same for the ECU relay (or DME as it seems to be called?) but I'm not certain that it's had it.

Ultimately, I'm getting a good cranking, fuel seems okay, I'm just not getting any spark. Coil is getting power, ECU is getting power, I'm pretty sure all the ground straps are okay. I've tried a HT lead straight off the coil, and that's not sparking either, so it's not the dizzy or the HT leads.

Possible culprit might be:

There doesn't seem to be a plug for the ICV? There's a 3 pin block, but it's been wired into the oil level sender (by someone before I owned the loom). Now this seems okay to me, as the FL oil level sender has a 3 pin connector on it, doesn't it?

I'm not sure if no plug in the ICV would cause the engine not to spark, I'd suggest not?

I've tried swapping the CPS and the CID connectors over, no joy. I tried putting the TPS block on the ICV, and that had no joy either.

Long and short of it is that I have no idea, and I'm now putting it out there as a call for help. If anyone who has done this before/is competent with auto electrics is free this weekend/any night in the week or any time in the near future, I'd be massively grateful if they could spend some time with me trying to sort it. My next option is paying for an auto electrician, which I'd really rather not do. That said, I'll be happy to pay someone if they're coming over to try and help, I don't expect anyone to just give up their time for nothing.

Anyway yeah, that's where I'm at for the time being

I have spare relays in the glovebox of the Baur, will try and come over to you in the next couple of days. Will be doing trackday prep on Monday but car largely ready, just need to stick the bonnet pins back on and get £100 worth of Nitro Vpower optimax or whatever it's called now.

Check you have power to all the pins needed for the ECU think it's 1 and 27. That was my mystery green wire in the loom. I know I've typed this AND told you about it in person, but this sounds like what my car was doing when I built it! Check the c101 from your donated loom and see if it has two green wires to the power pin, then make sure you have connected the small green up as well. Then we'll try the relays and swap the sensor wires until something happens. No ICV should not give a no start, but there must be a plug for it. You don't need the oil level sender, that connector may be the one for the icv.

Fuel pump relay won't fire if the ECU doesn't tell it to. It needs power to that extra pin in order to do that. My FPR didn't fire, and I thought I had a duff ecu till I found the extra wire.

Other than the power and relays, I suspect you will need to shuffle the fantastic identical connectors around between the various combinations until you hit the right one. If we get my car next to yours we can look at where the wires on mine run to, but as long as you try all the combinations and keep a list so you don't keep trying the wrong ones you may get there.

Can you PM or text me so I have your number. Have two numbers in my phone from the day you came round, not sure which is you!

You have a PM.

Yeah, I've connected the small green wire to a switched live, should it be permanent?

I checked the pins, 19 was live I think, with 18 and 24 both grounds, checked it and it was okay.

So the big news is that today the M20 started. It was somewhat unexpected but ultimately, it did.

It appears for some reason, the fuel pump relay isn't having it, and possibly the ECU relay, which I kind of already knew, so the only reason it started was because the relay plugs were bridged with some wire. So I need to try some known working relays and see if it's the relays, or the ECU not telling the relays the information they need.

While the engine was running for the second time, the oil line loop that I had made to join the outlet and return side of where the oil cooler was, exploded. The line had kinked, and the oil had backed up and caused the line to completely, and somewhat spectacularly fail. I'm hoping there was no damage done to the engine, as it was on for less than 10 seconds, and was idling. As soon as the line failed, the engine was turned off instantly.

The plan is to replace the oil cooler sandwich plate and oil filer housing with number 5 on this drawing:



It allows me to remove the oil filter housing mounting plate and oil cooler plate, then mount the oil filter directly to the block.

I'm unsure on if they M20 is okay without an oil cooler, but for now, I'm sure it'll be fine. If I do need one, I'll get on made up properly.

Once I've sorted the oil system, I'll be safe to run the engine for a little longer (there's no cooling system at the moment, so I can't leave it running for too long) but certainly long enough to establish how well it runs.

What I can say, is I noticed it idled better without the ICV, but it did idle quite high. When we plugged the ICV in, it seemed to idle worse, right up until the oil line exploded.

The injectors also seemed to buzz in a very pulsating fashion, they didn't do this all the time, only when the engine didn't start properly one of the the earlier attempts. It was a rhythmic buzzing, quite loud and was certainly "in sync" if you like, it wasn't a random buzzing. I need to look into that and figure out what was causing it.

Other than that, the engine sounded okay, no loud bangs or misfiring. Nothing to suggest at this point that the engine is a bag of spanners. Of course it is still early days so I'm treading with caution at the moment.

After the engine work came to a stop after the oil line failure, we decided to detail the car and get the oil off the paintwork. A full decon and claying, followed by Prima Amigo via DA and finished with Zaino Z2. Then all tucked up away on it's new part of the driveway.

Can't wait to make some progress on it now.

Okay, so the good news is the replacement relays seem to have worked, the car starts now.

New problem is that it's misfiring badly, sounds like more than one cylinder isn't right. HT leads are fine. Anyone got any suggestions. I've posted over on E30zone too.

I'm sure e30 zone will be helpful..........maybe! You are in the wrong section now. Are you a modified or 6cyl

They've actually been pretty helpful, Jamie!

You're probably right though, Jeroen, you fancy moving this to the Modified section?

So, I bought a new rad the other day, as the previous one was both the incorrect rad, and it also leaked.

Got it fitted today, just need the coolant hoses to arrive and I'll get it setup.



Then this weekend, I need to cut my splices out for the injector loom and resolder on the C191 plug which allows me to plug the injector wiring in via the OEM plug. This plug is a known water/dirt trap, but I want to get things as OEM as possible so I can eliminate anything that might be causing this misfiring.

I guess you can't get a bigger rad in haha! Looks good and I'll move the thread right away!

So yesterday the M20 ran and idled smoothly. Was idling a little high, but I'm assuming that's because the ECU hasn't learnt it's base idle settings yet.

It turned out to be injector wiring being all wrong, as soon as the new wiring went on, wired up to the C191 plug correctly, it started fine.

Exhaust next, and bleed the clutch/brakes so I can actually see if it moves!