Installing Mp3.1

[steely205 0]

I am about to commence on swapping the engine management on My 1990 1.9 from clock work to the

motronic setup I removed from a zx Volcane. I have been studying the Pin out diagrams and I am stump ed with the way I should tackle two parts.

 

Tachymetric relay, do i just use the jetronic Relay or replce it with the Double relay from the ZX?

 

And secondly the SAD, from the 205 wiring diagram in the Haynes manual it looks like it has a connection to the ecu which is not the case on the ZX diagram, it looks like it has a connection to the Double relay?

 

Any advice would be greatly appreciated so I can get on constructing the new loom.

[pug_ham 240 3 Cars]

You want to keep the whole of the ZX loom with the double injection relay & just find the wires you need to connect into the 205. All of the 205 Jetronic loom is removed.

 

I recently wired a 205 with a ZX loom which I extended it to keep the ecu in the standard location on the 205.

 

You only have to find four wires to connect between the 205 & ZX loom but two wires can see it running.

 

You will need either a convertor for the rev counter or modify one to fit from a suitable car. (The ZX one can be used, see this topic).

 

I have attached the page required from the ZX Haynes manual, you need to find the wires at the inner wing plug for the fuel pump (pin1 on the double relay) & an ignition switched feed to the wire from pin 14 on the relay (which also goes to the coilpack plug pin 4 iirc).

 

The SAD is an odd one on the ZX, it is fed from pin 9 on the double injection relay which goes on to the starter solenoid, when I wired it up this way the starter stayed engaged but the car had an extra relay for the starter fitted so this might've been why. I connected the feed to the SAD into the starter feed on the 205 & ran the wire from the SAD to earth, then it worked fine.

 

Graham.

ZX_MP3.1.pdf

[steely205 0]

Thanks for that Graham

 

In regard to extending the loom, is the Crankshaft Sensor Shielded and if so where did you get the wiring from to extend it?

 

I have the ZX clocks too, so the tacho should hopefully work[/size]Thanks again

[pug_ham 240 3 Cars]

In regard to extending the loom, is the Crankshaft Sensor Shielded and if so where did you get the wiring from to extend it?

It is sheilded, I was lucky that we have sheilded cable repair kits at work so I used the CAS wire I took off a car at the scrapyard & joined them up so the plug pins were in the correct as the wire colours were in a different order.

 

Graham.

[steely205 0]

Hi Graham, I had a look at the ZX loom when I got home last night and it could really do with replacing rather than extending. Most of the insulation is just flaking off, especially on the injector section of loom.

 

Looking at the ECU connector though it seems sealed for life? Is it a case of just pulling the pins out and drawing the wire with it? The problem with that is again going to be the CAS wiring which looks insulated all the way into the plug?

 

I am wanting to locate the ecu in the position of the jetronic so I will need a substantial length of shielded wire, any idea what vehicle could provide me with an adequate piece?

 

Also the map sensor vacum pipe, if it is pushed through the bulkhead gromet does this not cause a loss of pressure at the sensor?

 

Many thanks

 

Mark

[Super Josh 4]

You could get an Mi loom and use that. It locates the ECU in the standard place, so is long enough. It has a shielded CAS cable. You would need to lose the connection to the AFM, put in a wire for the Air temp. sensor. Not sure if the TPS plug will fit on the 3.1 throttle pot. but is should get you most of the way there. Maybe the 2.0 litre Mi loom would be better, or something of another later Pug. I would go to the scrappy and have a hunt around.

You'll be fine with the MAP sensor pipe going through the bulkhead grommet, just make sure you make a big enough hole, so that the pipe is pinched by it.

 

 

Josh

[steely205 0]

Thanks Josh, I'll have a look around the scrappy tomorrow and hopefully find a suitable doner for the CAS wiring. I think I'm still going to make a new loom though as the majority of the MI16 looms are of the same era and seem to get butchered by fitting immobilisers etc!

 

So are the ECU plugs generally reusable? If so is there a method of removing them successfully?

 

Is the method of crimping and then soldering the new pins okay?

 

Mark

[pug_ham 240 3 Cars]

Most of the insulation is just flaking off, especially on the injector section of loom.

The loom I extended was the same so I replaced all the injector loom & plugs with some from a 406 in the scrapyard.

Looking at the ECU connector though it seems sealed for life? Is it a case of just pulling the pins out and drawing the wire with it? The problem with that is again going to be the CAS wiring which looks insulated all the way into the plug?

There should be a screw on the end of the ecu plug that holds it all together, you should be able to get inside the plug. The wires fit into the plug from behind & wouldn't pull right through afaik.

I am wanting to locate the ecu in the position of the jetronic so I will need a substantial length of shielded wire, any idea what vehicle could provide me with an adequate piece?

Like Josh said, a 405 is the best as the CAS cable is plenty long enough if you can find one but an Mi loom has to many differences, even if its from a 2.0 Mi which had MP3.2 (the MP3.1 ecu wouldn't fit the MP3.2 plug). The loom on my car is from a 1991 405 SRi.

 

If not you can buy the cable from somewhere. This topic has some sources for loom wiring in.

Also the map sensor vacum pipe, if it is pushed through the bulkhead gromet does this not cause a loss of pressure at the sensor?

On the cars I've converted to run on MP3.1 there has been a small grommet in the bulkhead between the servo & inner wing that was ideally suited to the vacuum pipe, I don't think the length of the pipe makes any difference to the vacuum pressure.

 

The ecu loom shouldn't have been touched by someone fitting an immobiliser imo.

 

Graham.

[steely205 0]

Thanks Graham, I managed to open up the ECU plug tonight and finalised my pinning out, also got the Zx clocks apart for the tacho driver. Where did you mount the double relay on your install?

 

I'm trying to get everything together in the next couple of weeks so I can hopefully see her running over easter.

 

I'm planning on pulling the engine out at the same time, as I want to replace the valve stem oil seals and I should hopefully have a rebuilt box by then to put on.

 

I'm going to try Vehicle Wiring Solutions for my loom material, I think Polevolt do the CAS shielded wiring?

 

thanks again. no doubt I'll have a few more uncertainties as i'm going!

[Super Josh 4]

One other thing that I've just thought of. I'm probably stating the obvious, so just ignore me. You'll need to fit a flywheel with the timing teeth on it for the CAS. So either the one from the ZX, a later Motronic based 205, if you want to keep the 200mm clutch or one from a Mi16/GTi6 if you want to fit a 215mm clutch.

I'm surprised that this conversion isn't more popular. It really does bring the 205 into the 20th Century With a nice stable idle and extra driveability/mid range torque that mapped ignition gives you. Maybe people are put off by hassle of changing the flywheel? I would certainly have gone this route if I'd kept my 8V.

 

 

 

 

 

Josh

[steely205 0]

Thanks Josh,

I blew the diff the day before it's test last july, so I pulled the box off then and replaced the fly wheel with the ZX item. I used the diff and diff cover from the ZX and put the box back on and the car was reluctant to move, it felt like the brakes were binding, I checked the clutch adjustment as I know if it is over adjusted it will have a similar affect. The gearbox oil lasted all of 20 mins before it found it's way out of the new diff cover(It was a different casting to the GTI, it didn't have a locating dowel?) . And since that point I drove it into the garage and have started her every other week.

 

So I have stripped the ZX box to it's casing, I'm having it shot blasted and then i'll spray it, and fit new clutch arm bushes, input and release bearings I'm going to transfer the gear's from my GTI as I know they were great, and put it all back together. With new Management and box I hope I can start and enjoy my GTI again (Kids and wife permitting!)

[steely205 0]

It is a really cheep upgrade to, I paid £80 for the engine\box, ecu, loom manifolds, clocks ETC.

I had already tried re tracking the Air flow meter without any great success and a new airflow meter is £100 plus! So why not spend a little time and as you say create a car with a stable Idle.

 

I can't wait to try it!

 

thanks againg for your help

 

Mark

[pug_ham 240 3 Cars]

On the car I did last month with the extended ZX loom (which came from Toddman via super josh) I managed to get the double injection relay, mixture adjustment pot & ecu all in the opening under the dash where the ecu is normally fitted on the 205 keeping it all nice & neat.

 

Graham.

[welshpug 1,621]

dragging this one up any update? getting more and more frustrated with Jetronic

 

any chance of getting someone to do a loom for me to plug in a la PRD's Mi16 plug in looms??

[pug_ham 240 3 Cars]

any chance of getting someone to do a loom for me to plug in a la PRD's Mi16 plug in looms??

I could possibly do it but if you can't get your head around this simple wiring conversion you'll be super stumped by the GTi-6 one you are trying on your ZX.

 

Are you wanting to keep the ecu in the standrad 205 placement or in the engine bay like on the ZX? ZX method is far easier but for me to do the loom you'd need to take the car off the road to send the old ecu & guages wiring looms fromt the brown plugs under the dash.

 

Graham.

[welshpug 1,621]

I dont mind where the ECU goes, I guess if it goes in the ZX position theres a nice box for it to sit in.

 

As for the 6/zx16v wiring that is reasonably straightforward, though I may still need assistance I guess I've found my weakness in working on pugs and its not a good one considering their rep!

 

may take it off the road sometime soon as it's really annoying now!

 

It cranks fine, stinks of fuel, but no spark and the rev counter doesn't move like they normally do, bastard thing drove fine this morning!!!

[pug_ham 240 3 Cars]

From what I've seen the MP3.1 will be far easier to install into a 205 than the GTi-6 into a ZX imo.

 

Graham.

[welshpug 1,621]

right, I will go hunting for the loom!

 

car is sat 1/4 mile away outside a petrol station having got there then refused to re-start and i'm pissed off with it!

 

Everything bar the wiring has been replaced and its fuelling but I there is no life from the rev counter as it cranks, though it will give the occasional splutter and die again.

 

so I need, ECU, complete engine loom and double relay, coilpack and thermostat housing that bolts to the end of the head.

 

Would it help if I got hold of a loom from a 205 so I could do the wiring then just plug it in in place of the original one?

[pug_ham 240 3 Cars]

Have you checked the plug to the dizzy field windings from the ignition amp? This can get wet & corrode which stops the spark very well.

 

Choice is yours, if you can get a 205 loom from the plugs under the dash (has your car got these? ) then its easier to make up the new one but didn't you fit the superseal connectors in place of the engine bay brown multiplug?

 

You need;

• ECU
  
• Loom with all sensors (MAP, CAS, IAT, TPS)
  
• double relay
  
• suitable inlet manifold with map sensor pipe & a TB the TPS fits
  
• toothed flywheel
  
• Thermostat housing & coilpack with leads
  

Graham.

[welshpug 1,621]

Have you checked the plug to the dizzy field windings from the ignition amp? This can get wet & corrode which stops the spark very well.

 

Choice is yours, if you can get a 205 loom from the plugs under the dash (has your car got these? ) then its easier to make up the new one but didn't you fit the superseal connectors in place of the engine bay brown multiplug?

 

You need;

• ECU
  
• Loom with all sensors (MAP, CAS, IAT, TPS)
  
• double relay
  
• suitable inlet manifold with map sensor pipe & a TB the TPS fits
  
• toothed flywheel
  
• Thermostat housing & coilpack with leads
  

Graham.

 

thanks graham, one thing for me to try! the dizzy and fly lead is brand new, so I guess it could be the short bit to the amp thats playing up.

 

I did indeed fit a superseal connector in place of the brown multiplug in the engine bay, but seeign as it comes apart easily and the individual components are replaceable it'd be easy enough to disconnect it and re-use the plug.

 

I have an Mi16 flywheel and clutch already as I've been gathering info and have started collecting parts!

 

thanks

[pug_ham 240 3 Cars]

Just had a thought Merion, is your gearbox a be1 or Be3?

 

If its a Be1 best check it has the CAS hole on.

 

Graham.

[welshpug 1,621]

it is a BE1, but it did have a TDC sender for diag purposes plugged into the box as these do, but if thats no use I do have a BE3 box in the shed

 

been having a further fiddle, the AMP side of the dizzy-amp wiring is fine, no corrosion and continuity is fine, though I think I'll get some small connectors to make up a short section to bypass this wiring, and where the engine loom goes under the intake manifold doesnt look very tidy so I'll take the manifold off and check it all out under there.

 

both sides of the coil have power.

 

checked under the dash for the 2 multiplugs on the loom that goes to the engine bay from the ECU and they are present

[pug_ham 240 3 Cars]

it is a BE1, but it did have a TDC sender for diag purposes plugged into the box as these do, but if thats no use I do have a BE3 box in the shed

The CAS is a different type & uses a totally different hole than the one fitted for diagnostics.

 

You need to have the hole thats near the front of the block on the gearbox (between the top two bolts that are holding it to the block).

 

Graham.

[welshpug 1,621]

aah, I did wonder, I couldn't remember exactly where the hole was on the BE1.

 

can I use that or is the hole in totally the wrong position?

 

I have an early BE3 that I can use, I say early as it has the BE3 style clutch release arm and release bearing but still has the hole on the front of the box for the BE1 mechanism.

[Guest Eduard205GTi]

Hi all,

 

My AFM is slowly breaking apart I would like to go the "upgrade"-way.

Read a lot about the Motronic 3.1 fitment to a 205 GTi. Pugtorque is using the system of 405 SRi ? (correct me If I'm wrong). Is this off the 2.0 or the 1.8? I can get my hands on the set of 1.8 SRi. Can that be used?

 

Regards,

 

Eduard