swindon_alan

@Kevin Wheeler sorry, just realised that I cocked that up! I moved your post to the correct forum but the link should say: Giugiaro thread

No problem Kevin! There might be some clues in that thread though?

Stevens thread

Thanks Michael for the suggestion. Perhaps a slight misunderstanding here though. I'm ok with the 88 pin 918 ECM connectors, I can get Bosch pcb mount lookalikes from China for about $25 each. I can even source the plugs, although quite pricey I won't need many of them (only for dev/test). The twin pairs of keyed 22 pin connectors I was referring to are for the SE onward 4 pots, which appear to be unobtanium!

As above @Barrykearley, I only found out tonight from who I shall call a very well informed source that EFI developed the ECM for Lotus from scratch and then modified it to sell on the open market as the MT-501 (different case, some connection differences, obviously no Lotus proprietary content). I was advised to look at the EFI Euro-4 as an alternative that is in production. Price to you Mr Kearley? (although you don't need or want one!) £2,100 Including VAT. Then all of the pain of setting it up. Nope, my ECM target price is well under a grand...

Hello Michael, I have just received some interesting info on the factory ECM. It isn't in fact a programmed EFI MT-501 as I thought but a custom version specifically for the V8 which EFI subsequently modified and sold as the MT-501 (!) Having said that, I'm convinced that it is similar internally and you are quite right, there are eight individual ignition coil circuits but only two are used. So by default there were eight but with multi-coil packs Lotus didn't have to use the other six.

Stevens Direct Ignition Module, A910E6940F (ex-coils)

Ooh I can actually incorporate the nitrous thingy. Kicks in when you floor the throttle at low revs to spin the turbo up in no time at all. Gonna do it on my MG Metro Turbo'd classic Mini. Ian, Ian, Ian, please say yes...

Are they potted Derek? Or just have a nasty lid like the KH EBCs? How to remove epoxy potting (assuming that the chips can all take a 100C "storage" temperature).

@Sparky please can you confirm my suspicion that Ian craves massive overboost, water injection and launch control on his S4s? Only because he is running out of other things to fix/break on his car along with his ambition to drag it at Santa Pod?

I think Derek is well on the case with that one Ian. Not sure I could assist much unless I could have one to take apart (as Derek wants to do anyway). EDIT: @sailorbob Have you seen this post Derek? Choice 2: add an internal jumper so you can use a GM DI module? This is probably not for this forum might move these to Stevens...

So it is also a good job that I have a password cracker then Derek! Assuming that it doesn't have much in the way of a defence (time outs/lock on fails etc.)

I suspect that your suspicions are correct Derek: The MT-501 has those pesky ST M29F010B 1Mbit EEPROMS in PLCCs that you have to remove, fit sockets and replace if you want to change the maps. Taking a cue from Esprit Engineering: Now I know this (and we have a Write Enable line identified), I reckon there's a possibility of doing the reprogramming myself without opening the ECM up. This is the pin out from the EFI wiring loom that has multiple connectors for this, a dashboard and a data logger - all using CAN. Easy enough to knock up an interface cable. Also digging through the documentation and thinking about it, the K-Line and CAN data streams both use pin 72 on the ECM/pin 7 on the DLC connector. The CAN_H/CAN_L and WR EN are used to enable this (but again, only on the rear DLC connector). I wonder if I can get hold of the original MT-501 utility software, it comes on a "single high density floppy disk" apparently. Good job I still have a 3.5" FD USB drive..!

On the subject of OBD sockets, I have long been slightly mystified by the additional three wires on the rear (boot) connector. The front one doesn't have them? In the course of digging around on my Kelsey Hayes EBC work (and connections to the ECM) I came across what I believe is the answer. This is from a third party (non car model specific) EFI MT-501 document: In the OBD2 spec these pins are listed as "manf. discretion/OEM reserved". Now, as the MT-501 natively supports CAN, I'm thinking that perhaps Lotus either implemented CAN or put the connections in for potential future use, as the later spec was an incoming preferred standard in 1996. So as well as the the K-Line Protocol Numbers 4 and 5 on pin 72 that we all use with ELM 327 adapters there might be an alternative high speed interface. Another option might be that it was used to upload the V8 specific configuration into PROM. Something to chew on. I might investigate further when Nelson gets his eye back. Anyway, mystery solved for now.

No, not taken as sarcastic at all! As you can see from this post, the EFI MT-501 ECM that the V8 uses has a lot of integration with the abundant car systems. It's not just a question of whacking in an aftermarket ECU that will run the ignition, fuel injection, boost and so on. It also has to drive the speedo, tacho, aircon, recirc relay, radiator fans, engine overheat lamp, the CEL, plus all of the OBD gubbins etc. The other problem is that Lotus has never released the maps for the V8 so setting up an Emerald etc. requires a lot of dyno time to get right. I give you this thread, just adding a Megasquirt looks fun but not straightforward. Numerous owners have gone down the aftermarket route and fair play but the investment in time and money looks to be substantial. The aim is to develop a like-for-like drop in replacement with some extra bells and whistles (if desired). Hope that makes it clear!

Hello Derek. No, I understand that. My thinking is more along the lines that the V8 version I am developing will have added optional wow - launch/traction control, water injection, dial-a-boost and so on. It would be relatively easy (!) to change the software and interface board for a four pot. Sure, it is quite a lot of effort but then I find it fascinating and a challenge. As i have noted elsewhere, the biggest problem will be sourcing the two 22 way pairs of keyed PCB mounted connectors. I can't find them anywhere! Unless someone else knows?

@Barrykearley What's your thinking Barry? If that in the longer term there will be a dearth then I think I agree with you? PS can you post in my poll please, I'm not sure if it works or not... Ta Yup and thank you for that Filip. It is sat on my "To Do" shelf. As per Derek's post on the Stevens forum the 4 pot isn't as urgent as the V8. The biggest problem I am going to have with it is sourcing the connectors, two pairs of 22 way keyed and I can't find them anywhere!

Esprit Engineering repair and exchange offering. (It's on the V8 forum but applies to Stevens Esprits as well).

Poll attached and refers to this post.

One of our Esprit specialists looks to have spotted the gap in the market as far as ECMs are concerned. As we all understand, replacement V8 ECMs are just about non-existent. Mike S in Germany knows someone who can repair them and there might be a few other places around. I hadn't noticed this before but Esprit Engineering down the road from me in Salisbury formalised a repair and replacement offering a year ago (both 4 pot and 8 pot ECMs): The prices are pretty good too, compared to having a completely useless Esprit sat on the drive: As to whether they sub these out to someone like Bluestreak Electronics, ano or they have in-house expertise is a moot point if they can get them fixed. Also as an Approved Lotus Heritage Repair Centre they probably have the inside track on the internals and factory test gear (e.g. TECH-1 scanner and module for the V8). I think it is brilliant! As some know, I have been slowly working on my own low cost V8 (and eventually 4 pot) ECM, I'm probably about 20% of the way there. This makes me wonder if it is worth continuing with the development? Time for a poll perhaps.

@march aha! That is EXACTLY what I need Marc! I am going to develop the software to talk to the ABS ECM. Are you up for helping me? It will only require you to download and run a simple comms utility program against the instructions that I will provide. Then once I have proven the interface I can write the application and of course you will get a copy! This is not mega urgent by the way, I need to do my KH415 first to prove that it is possible. So it is not imminent.

I think by opening the boot she's shown a couple of small booboos?

@march Hello Marc, a Happy New Year to you. As above, I'm looking to put a KH415/KH430 diagnostics etc. app together. I can develop and test against the KH415 on my '96 V8 but I will need some help with the same against a KH430. I'm assuming that your post '98 has one? If so, have you got a DLC/ELM327/PC interface that you use for e.g. Peter English's V8 ECM diagnostics tool? We can take this offline to IM if you can assist. Thank you sir.

Nah. Present owner screwing the wastegate down...

@sailorbob is your man I would have thought?