MI16 wiring help - No spark

[Omorgan 1 1 Cars]

Hello all, 

 

I've been reading and reading and reading on here about similar issues however my issues seems to be slightly different to any I've seen.

 

I have a base model 1.1 205 which has all GTI bits on it and I recently bought an XU9J4 MI16 engine which I've fitted. The issue comes with adapting the MI16 loom to work on a base model car with no original loom and I can't make the thing spark. The engine was previously in a 205 GTI so it has already been messed with which isn't helping.

 

I've installed a brand new Crank position sensor, which is working with the Pug1off billet 405 flywheel and the resistance between pins 1-2 is in spec.

The dizzy cap all looks good underneath

 

The coil wiring has been confusing me and I've been following @DamirGTI's posts but I still don't get spark.

 

I have the AFM plugged in, the TPS, the coolant sensors, ECU switched live (that works while cranking), the other end into the shunt box, The coil and the coil amplifier.

 

Issues - 

I have two plugs which I am unsure of there purpose and dont look OEM to me. (Last 2 photos)

I am running the base model starter relay and wiring, and I'm unsure if the ECU needs to see the MI16 loom starter relay active to spark and inject.

I have jumped the fuel injection relay and fuel gets injected and I can hear them buzzing on 2nd stage ignition.

 

The small white 2 pin plug contains what I believe to be a tacho wire and a ground. I'm not running a tacho yet so I dont know what to do with the turquoise wire. 

 

To be honest I reckon I'm not the man for the job and maybe if anyone who knows what they're doing might be able to give me a hand for cash in Southampton UK that would be greatly appreciated

 

 

 

 

[petert 586]

Which ECU does it have? I have wiring diagrams for both types.

[Omorgan 1 1 Cars]

It's got the Bosch Motronic 0 261 200 125.

 

I've been using the XU9J4 diagram from the 405 so maybe the same one but anything will help, cheers.

[petert 586]

That’s the same one I have for that ECU. Connect it up as per that and it should work.

[Omorgan 1 1 Cars]

I'll have another go, but might be time for an auto electrician to take a look

[Omorgan 1 1 Cars]

After more research, I bridged both the starter and tachiometric relay and got spark. I can leave the starter relay bridged because I'm using the standard 205 one, but require a new tach relay. Does anyone know an alternative relay or what to look for? The OEM ones seem to be extremely expensive.

 

 

[petert 586]

The 405 doesn't use a tachymetric relay. It has a normal relay for the fuel pump, controlled by the ECU. It's in the black, plastic box, along with the other +12V control relay. Thus you need to bypass the original tachymetric relay. You'll have two fuses however. The original in the glove box and the 405 fuse in the black box with the relay (highlighted below). Make the 405 fuse higher, say 30A, so you're not chasing your tail if one blows.

 

Edited April 30 by petert

[Omorgan 1 1 Cars]

Ah okay, that explains why I could find any. I noticed that the trigger wire from the relay lead to the coil. So am I right in saying that when it detects rotation the relays pulls to ground and allows the injectors to work?  I've put a standard relay in place but it's always live in position 2 key, not even cranking, injecting loads of fuel into the cylinders. I was hoping this was because I'm using the wrong relay. The other issue is that I'm running a separate fuel pump relay off a switched live which seems to making things more confusing.

( I appreciate your help - thank you)

[petert 586]

If wired correctly, the fuel pump won't trigger until a tooth on the flywheel passes the crank angle sensor.

[Omorgan 1 1 Cars]

Okay thank you for your help Peter

[welshpug 1,657]

205 nor 405 have a starter relay.

[DamirGTI 342]

11 hours ago, Omorgan said:

I've put a standard relay in place but it's always live in position 2 key, not even cranking, injecting loads of fuel into the cylinders. I was hoping this was because I'm using the wrong relay.

 

 

Indeed it is , wrong relay type ...

 

Standard 5pin relay wont work , you need 5pin "dual output" type : Bosch 0 332 019 150 .

 

D

[DamirGTI 342]

On 4/29/2024 at 8:05 PM, Omorgan said:

 

 

 

 

 

 

Coil wiring doesn't look connected/soldered correctly , should be colour to colour ie. pink on pink , blue on blue , yellow on yellow etc. .

Mi16 uses same square coil type as 1.1 TU .

 

Fuel pump relay type and coil wiring is you're problem me thinks .

 

Crank position sensor - there was an batch of new Bosch sensors for XU and EW PSA engines recently , which where faulty from the factory (they messed up sensor wiring polarity) , if i remember last three digits where *120 , and it was Made In Turkey .

 

D

Edited May 1 by DamirGTI

[Omorgan 1 1 Cars]

Thanks for your input Damir. I have spark now with that wiring looking as bad as it does. It was clearly hacked together by the previous owner but it does seem to work so far. I appreciate the relay advice, I'll have a look and see if I can get one ordered.

 

I managed to get spark by jumping the green relay (which i incorrectly assumed to be starting relay) and now the car starts.That suggests to me that the crank position sensor is good.  I'll see if the relay you suggested will only inject when it detects rotation because that will then sort my issues.

 

Thanks,

Owen.

[SRDT 175]

4 hours ago, DamirGTI said:

 

Indeed it is , wrong relay type ...

 

Standard 5pin relay wont work , you need 5pin "dual output" type : Bosch 0 332 019 150 .

 

D

It's a dual output relay on the schematics but pin 4 is unused so a regular relay should do.

 

Here is the ECU and fuel pump relay setup from a 35 pin 405 in more detail, a loom from a BX 16 Valve or 309 GTI16 may vary a bit regarding relay type and location.

[Omorgan 1 1 Cars]

I appreciate all your feedback. I'll install the new relay and see how it behaves. So far I can still only get the car to start and run for about 1-2 seconds So I need to look into why it doesnt idle.

 

https://www.youtube.com/watch?v=SgStuD41TQY 

 

Loud because the exhaust consists of a manifold and nothing else. And yes I'm actuating the throttle with my mouth

 

[petert 586]

As I said earlier, you need to bypass the tachymetric relay, as it's duplicated in the 405 relay box.

[Omorgan 1 1 Cars]

1 minute ago, petert said:

As I said earlier, you need to bypass the tachymetric relay, as it's duplicated in the 405 relay box.

The engine and loom are in a base model which I don't believe had one. Maybe I'm wrong. The base model car had no engine loom. I have spark and fuel now, but only when I bridge the injector relay until hopefully my new one arrives. Am I misunderstanding?

 

Cheers, Owen.

[petert 586]

Back at the very start, you said "The issue comes with adapting the MI16 loom ".  By that, I assumed you have a 405 Mi16 engine loom, complete with ECU. In that loom, approx 1m from the ECU, is a black plastic box with two relays and some fuses in it.

 

Could you please confirm that?

[Omorgan 1 1 Cars]

Yeah that's correct

[petert 586]

Have you found the fuse M477 and joined wire 76 directly to the fuel pump?

[Omorgan 1 1 Cars]

I know where the fuse is but i'm running the fuel pump on a separate relay with a switched live trigger. Do you think that's going to be an issue?

[petert 586]

Yes. That is most likely your problem. SRDT posted the OEM wiring diagram above. It MUST be like that. FInd the original #76 wire coming through the firewall, from the 205 fuse box and fuel pump, and connect it to wire #76 (and fuse M477) in that box. I'm not sure how much clearer I can make this.

[Omorgan 1 1 Cars]

No I understand you and I appreciate you helping me even if I seem slow. However the base model car had no fuel pump, just a vacuum feed so I've changed to a GTI tank and installed a pump. Therefore there is nothing in the fuse box for a fuel pump and I assumed that running a separate fuel pump relay would be fine. When I get home I'll change my wiring from the switched live feed to wire #76.

[petert 586]

Ah, sorry for being short with you too. We only have fuel injected models in Australia. You basically have to recreate a 405 inside a 205 shell.

Edited May 2 by petert