mi16 on 8v motronic management?

[FauxRallye 4 1 Cars]

A few  months ago I purchased an mi16 engine together with a wiring loom and ecu that had supposedly run in a different 205 already.

Recently after alot of headaches and trying to figure out the plugs on the loom I've found out that it's a loom from a dkz engine and an ecu from a bx 1.9.

I've seen mentions on the forum that this was sometimes done back in the day, so I'm not too worried about using the loom and ecu to swap the engine into my car in two weeks.

But what are some things to look out for?

I can't imagine the idle will be too amazing without the idle control valve connected (or do I just plug the sad plug into it?).

Any helpful knowledge is appreciated

[petert 550]

The DKZ loom is 3 row. The BX1.9 ecu could be 2 or 3 row, you didn't say. The only differences between a DKZ loom and a 3 row Mi16 loom are:

1. knock sensor (if fitted)

and

2. Idle control valve

 

All the 3 row ecu's have an O2 sensor, whether 8V or 16V. I have outlined the differences here:

http://www.taylor-eng.com/ecu/motronic_intro.html

 

I have successfully added both knock sensor and IAC wiring to a DKZ loom, then fitted either a 158 or 161 ecu for a very neat conversion. It's not hard to do if you have the knock sensor cable. The IAC is super easy, as it's only one wire to add. Power for the IAC comes from the injectors, which are close by.

 

Your easiest solution is to find a 354 or 355 ecu and just add the IAC wire. I've posted the wiring diagrams many times but can do it again if needed.

 

 

 

[FauxRallye 4 1 Cars]

ah alright, I'll try to find an 158 or 161 then.

The ecu I have right now is 162 3 row ecu.

I hope I can find an ecu in time for the swap, because that will happen in about two weeks.

Adding three wires to the harness can't be too hard I think, gotta find the correct cable ends to fit in the ecu plug though.

 

If I can't get one I'll just see how it runs with the ecu I have and change it at a later date.

And if all else fails I've still got an old link ecu lying around, but that'll be a lot more work than adding three wires.

[petert 550]

158/161 means you want a knock sensor? Are you sure? The knock sensor cable is 2 core, shielded, like microphone cable.

eg

https://www.motorsportelectrics.com.au/shop-by-product/product/tefzel-screened-wire

 

The 162 was fitted to DKZ.

 

As I said, easiest for you is 354/355. A 158 or 161 without a knock sensor will go into fault mode and severely retard the timing. Driveable though.

 

Edited November 26, 2023 by petert

[petert 550]

Another option I just thought of, but haven't tried, is to fit a 355 chip to the 162 board. It won't be looking for the knock sensor, so theoretically should work. I could burn you a chip and post it, but no guarantee on two weeks.

[FauxRallye 4 1 Cars]

Hmm that would be awesome, but I'd lose the functionality of the o2 sensor then, right?

Although that shouldn't matter too much if it still hits the right emissions numbers

[petert 550]

No, O2 sensor is in both 162 and 355. Exactly the same pin outs and wiring. You will only need to add one wire for IAC, optional anyway. If you block or remove the IAC, and adjust idle manually, it will run fine.

[petert 550]

FYI, the IAC needs approx. 2V to be fully closed. If it is disconnected or 0V, the valve will be slightly open, resulting in an idle of approx. 2000RPM, giving limp home ability.

 

I'm out of chips, so I'll need to buy a chip from retail, but can still get one in the mail today. Send me your details via message.

Edited November 26, 2023 by petert

[SRDT 146]

Isn't 355 the non cat version? I can assure you that my 309 whith 3 row ECU and knock sensor has no O2 sensor nor evap canister.

 

As for the 354/355 chip it should be expecting a knock sensor, isn't that why you can use 95 octane fuel when a 2 rows ECU need at least 98 octane?

 

You can find the 309 wiring diagrams here:

 

http://ddata.over-blog.com/4/23/45/11//Schemas-Electriques-309.pdf

 

85/118 is for XU9JAZ and very close to the 205 wiring, 86/118 is for XU9J4 with dotted lines for the XU9J4Z variant.

 

For the 354/355 ECU you may need to add a wire to the AFM if it's not there, the internal CO pot isn't used with Lambda.

[FauxRallye 4 1 Cars]

2 hours ago, petert said:

 

All the 3 row ecu's have an O2 sensor, whether 8V or 16V. I have outlined the differences here:

http://www.taylor-eng.com/ecu/motronic_intro.html

 

In the link you posted it says the 355 has a knock sensor, but no o2 sensor.

I'll shoot you a message tomorrow, because I have to get up for work in about 6 hours

[petert 550]

Yeah, can’t even read my own stuff. Thus you’ll need to add a knock sensor regardless. In which case, you may as well try one of my special chips, based on 158/161 rather than 355.

[FauxRallye 4 1 Cars]

Wouldn't it be possible to put the fuel/ignition map of a 161/158 on a 162 chip? You'd effectively have a 161/158 chip without the knock sensor then, if that's possible. 

Also still without the iac, but I'll take that out and plug the ports anyway.

Edited November 27, 2023 by FauxRallye

[petert 550]

That's actually a really good idea, but I don't have the brain cells to do it.

[FauxRallye 4 1 Cars]

aw man I'll try to find out if there's someone here in the Netherlands who can do that. I know some guy who used to drive rallys with 205s, maybe he'll know someone.

Otherwise I'll use the 162 ecu and see how it runs. If it runs awful I still have all winter to get it running on an old link ecu I have

[petert 550]

Don't drive it hard. It will run lean on the 162. I have done it before.

[X-mo 17 2 Cars]

Hi there,
build my 205 Mi16 with a DKZ (3-row) loom and added the needed wire to get the Mi16 management (3-row) working. It's not that difficult as you only need to add one shielded wire to your loom and change some Pins at the ECU. It

Here is the description from our German forum "French-Classics.de":

 

knock sensor:

Pin1 - Knock sensor -->  Pin11 - ECU
Pin2 - Knock sensor -->  Pin30 - ECU
Shield --> Pin14 - ECU

Idle control valve:

Pin1 -  Idle control valve --> Pin4 - ECU
Pin2 -  Idle control valve --> Pin2 - Fuel exctraction relay (just add the cable to the Pin2 of the relay, so there are two cables at Pin2 - cable Nr. 20E)

 

Hope it helps you.

[FauxRallye 4 1 Cars]

Thanks,

I'll do it like that if I can get my hands on the correct ecu in time. 

I'll run without the iac, but the knock sensor is essential with those ecus.

 

I've found somewhere I can get the shielded cable, but where do I get the cable crimps that go into the ecu connector?

[FauxRallye 4 1 Cars]

Ha! Found the pins and connectors I need on AliExpress of all places. Won't be here in time for the swap, but it shouldn't be too hard to add those  afterwards I think

[FauxRallye 4 1 Cars]

I asked around in the dutch facebook groups and I may be able to get my hands on the correct ecu, fingers crossed.....

[petert 550]

Here is a diagram from one I did previously. Let me know if you want a 7500 chip.

 

M9 - IAC

M132 - Knock sensor

Edited November 28, 2023 by petert

[FauxRallye 4 1 Cars]

nice that's a handy diagram. 

A 7500 chip's definitely tempting, but I want to get the car running first before doing anything performance related.

Do you by any chance have a good picture of the standoff the knocksensor is mounted on?

I have d6c block so it doesn't have it and I can't find any good pictures online to replicate it.

[Thijs_Rallye 86 4 Cars]

15 hours ago, FauxRallye said:

I asked around in the dutch facebook groups and I may be able to get my hands on the correct ecu, fingers crossed.....

I can't imagine there aren't any ECU's for sale somewhere in Europe. I answered your post on facebook :).

[FauxRallye 4 1 Cars]

Already writing with someone who said he should have one, from a 309 gti16 with cat. So I'm 99% sure it'll be the right one, he just has to check the number on it first

[SRDT 146]

D6C engines also have the standoff and knock sensor since model year 91 and the transition to ML1.3 Motronic.

21 hours ago, FauxRallye said:

Do you by any chance have a good picture of the standoff the knocksensor is mounted on?

I have d6c block so it doesn't have it and I can't find any good pictures online to replicate it.

I will see if I can find you a rough sketch blueprint.

[petert 550]

This.