Last Few Issues With My Mi16 Conversion

[axnutty 10]

I've got my Mi16 installed and it seems to be running nicely now but i'm just trying to finish things off and clear up the last few wires. Following on from this topic I posted in the wrong forum area could anyone shed some light or places to focus my attentions on?

 

 

It's a ML4.1 system as it has no knock sensor and I'm pretty certain its a BX derived 16v engine as the cam end cover is open like a hydraulic pump has been removed and its a steel sump.

 

Under the dash the 2 brown plugs are wired as follows:

 

 

9 PIN BROWN

 

1 Reverse Light

2 Reverse Light

3 Coolant Light

4 Coolant Meter

5 Alternator

6 Oil Pressue Meter

7 Oil Temp Meter

8 Oil Pressure Light

9 Switched Positive

 

 

6 PIN BROWN

 

1 Not Used

2 Fuel Pump

3 Earth

4 Tacho

5 K Light (not used)

6 Starter Motor

 

 

However I have a number of issues and questions regarding the last few loose wires etc.

 

Question 1:

 

In addition to the plugs I have 4 loose wires from the engine loom (labelled A to D in the diagram). I believe A & B (2 small blue wires) to be the oil level feeds and not used in the conversion <- Is this correct?

 

Question 2:

 

I have 2 large white wires (C&D) that give a +ve reading (like 12 / 13volts +ve reading) when running which are currently not connected <- What do these do and are they connected to Q3...

 

Question 3:

 

The Injection relay is currently hard wired as the primary arming cicuit is recieving no power when the ignition is switched on. <- Why would this be?

 

 

 

Question 4:

 

There are 2 spare wires coming from the ECU area. One is an Earth and one is a +ve feed... are these for diagnostic purposes and left disconnected?

 

 

Question 5:

 

It seems I have no feed for the tacho!! <- Any ideas!!

 

Question 6:

 

There is a spare wire at the coil from pin 4 <- where does this go?

Edited November 5, 2008 by pugtorque

[pug_ham 244 3 Cars]

With regards to questions 1 & 2; Any idea where in the loom these wires come from, especially C & D? Are they permanently giving 12v's or just when the engine is running / ignition on?

 

One of the two small wires could be your tacho signal, that should come from the coil plug, pin 2 iirc.

 

The injection relay is switched from the fuel pump relay iirc, thin green wire by the thicker yellow in the picture below loops from that plug to the other. BTW, my loom has the brown relay where your green one is.

 

I'll try to have a look at my BX loom better tomorrow (up @ 4:30am) to help with some of the other wires but this topic might help a little.

 

Graham.

[DrSarty 90 1 Cars]

Graham will help you no doubt.

 

My reaction is, you actually only have 2 problems; the others are just extra wires you're believing you ought to connect. If it works, I wouldn't bother. I'd just tape 'em up and label 'em, as you may find them useful (particularly if they're 12v perm/switched feeds or earths) in the future.

 

Your REAL issues are no tacho and your injector relay(s) being bodged in.

 

(i)

The latter need to be triggered to be on correctly as Graham said, most likely triggered by the tachy relay. However, my BX16v ECU had a single yellow wire exiting which was separate from the main plug and was the fuel pump control, i.e. going to white wire 76 in the brown multi plugs. What I'm saying is the BX16v ECU/loom conversion should not need a tachy relay anymore. What does the Haynes book of lies say for the injector relay(s)? I suspect it's just a 12 switched live, so you could most likely use one of your A-D wires for that (?).

 

(ii)

IIRC, part of the BX loom near the coil has a green wire and a yellow wire going to a 2 pin, white plastic plug. One of those - the green IIRC - is the tacho feed.

Edited November 5, 2008 by DrSarty

[pug_ham 244 3 Cars]

(ii)IIRC, part of the BX loom near the coil has a green wire and a yellow wire going to a 2 pin, white plastic plug. One of those - the green IIRC - is the tacho feed.

this plug Dr S? Picture from other linked topic.

 

I'm pretty sure thats how my loom is marked up, rev counter & fuel pump wires in that white plug.

 

Graham.

[mr_exe 1]

The rev counter is driven via coil and the ecu, see if wire 112 is connected properly

[pug_ham 244 3 Cars]

The rev counter is driven via coil and the ecu, see if wire 112 is connected properly

The ecu has no direct connection to the coil, it does with the igniton module but not the coil.

 

I've just looked at my BX ML4.1 loom & it also has the same wires by the ecu, the green one comes from the ecu plug pin 15 & although its not mentioned in Autodata, I've a feeling it could be the K light wire.

 

I've also got a yellow wire near the ecu plug along with the two grey wires into the red terminal, one of which comes from ecu pin 5 which autodata says is an earth but I can't find where the other wire into the red terminal comes from although I can see it heading into the loom away from the ecu plug.

 

I agree with the findings from Jas-E's topic that the yellow wire in the white two pin plug is the main ignition switched feed for the loom as it bells out with the ignition module, coil, fuel pump / igniition relay & fuel pump feed yellow wire near the ecu plug. The green wire in the same yellow plug only goes to the coil plug pin 2 which I believe is the rev counter signal.

 

My Haynes diagram shows that injection relay is directly conntected to the shunt box & my loom matches this as the fuel pump is connected to the ignition switched live (yellow wire mentioned before) with small green wire linking to injection relay closing it when ignition is switched on.

 

Graham.