Mi16 2row Wiring Help

[unariciflocos 49 1 Cars]

Right... after rebuilding my Mi16 and taking the car for a spin I decided to pull out the mess of wires and sort the loom properly.

 

There was one connector that was hanging about, of which the former owner told me it's got something to do with the ABS. After taking the loom off I found that it's actually the ignition amp connector, and I've been running the car without it. Is that possible? I mean of course it's possible since the car runs, and runs as it should, but should I add the ignition amp ?

 

There's another 2 wire connector in the fuse box, looks like an injector connector and has a yellow and light blue wire. Does anyone know what that's for?

 

Thanks,

ANdrei

[pug_ham 244 3 Cars]

Did a previous owner left the 8v loom in the car & put the Mi one in as well jsut usign the four wires needed to plumb it into the car?

 

That's about the only explaination for a spare unused ignition module plug imo because to run it must have one connected somewhere.

 

No idea about the fusebox connector presently, what colour is the plug & do the wires have numbers?

 

What was the original ecu?

 

Graham.

[unariciflocos 49 1 Cars]

I personally took the engine out of the previous owners' 405 Mi16 and believe both the loom and the ECU are genuine 405 Mi16 ones. Don't have the ECU with me, I left it in the car which is stored some 30 kms away.

 

The connector in the relay box is black and I have not found any numbers on the wires. I have found numers on some of the other wires, but these one don't have any and seem to be too thin for any markings. The battery on my multimeter died so I can't check to what pins in the ECU plug they go to. Not too worried about that though... just want to tidy up the engine bay a bit.

 

Strikes me as a bit odd that the car would have an ignition amp connector but it would run fine without one. And it does run and pulls really well, even reached 140 MPH while overtaking a long line of lorries.

 

The car does run a bit rough on idle, with the odd hesitation, but I have that on poor insulation on one of the plug leads which lets the spark escape intro the head rather then the plug. I can even hear it discharge into the body of the head like some sort of ticking.

 

I appologise in advance for any possible mistakes or lack of coherence, but I've just arrived home from a concert and have had one too many drinks...

Edited February 27, 2011 by unariciflocos

[Alan_M 66 1 Cars]

Right... after rebuilding my Mi16 and taking the car for a spin I decided to pull out the mess of wires and sort the loom properly.

 

There was one connector that was hanging about, of which the former owner told me it's got something to do with the ABS. After taking the loom off I found that it's actually the ignition amp connector, and I've been running the car without it. Is that possible? I mean of course it's possible since the car runs, and runs as it should, but should I add the ignition amp ?

 

There's another 2 wire connector in the fuse box, looks like an injector connector and has a yellow and light blue wire. Does anyone know what that's for?

 

Thanks,

ANdrei

 

When you say fusebox, do you mean the relay box with the fuel pump relay in? If so, there is a diagnostic plug in there.

[unariciflocos 49 1 Cars]

Yes, I did mean relay box. That would make sense.

 

Still puzzles me how the car runs without an ignition amp.

[Ryan 99]

It won't. There must be one somewhere.

[unariciflocos 49 1 Cars]

There isn't one, I have the loom in my room spread out on the floor and I would have remembered or noticed one when removing it. I also may have had to notice it when reassembling the car after painting or when putting the engine back in the car after its rebuild.

 

What does the ignition amp do anyway?

[petert 588]

What does the ignition amp do anyway?

 

It earths out the coil, when triggered by the ECU.

[Ryan 99]

Just so we're clear, this is an ignition amp:

 

 

 

...and the engine will 100% not run without one, as it's what fires the coil.

Edited February 28, 2011 by Ryan

[unariciflocos 49 1 Cars]

I have a two row loom and had a 7 pin connector not plugged into anything. Car runs fine, does missfire on idle a bit and under acceleration sometimes, but I had that down to a faulty plug lead and the fact that I've raised the compression to 11:1.

 

The loom looked a mess, so I thought I've take it off the car to tidy it up a bit, and wanted to remove the said 7 pin plug, because the previous owner said it's ABS related. When i stripped the loom, I saw that two wires from that plug go to the coil plug, one to earth, and one to the ECU IIRC. Considering this I assumed the connector is for an Ignition amp. I have several spare and I'll connect one after I put the loom back and see what difference it makes.

 

However, the car did run with no ignition amp connected anywhere and all the horses seemed to be there. I personally took the engine out of a what I thought to be an original 405 Mi16.

 

I'll have to look into what each wire out of the coil plug is and does so that I can make some sense out of this.

[unariciflocos 49 1 Cars]

Update.

 

Put the loom back in, connected an ignition amp from my old 8 valve, primed the fuel pump manually (12 v directly on the pump) and then I turned the key. Engine didn't fire but I did see the smoke escape from the ignition amp and it got so hot that the backplate with the circuit board fell off. Took the ignition amp out and it fired straight up with absolutely no hesitation.

 

In conclusion, my Mi DOES run without an ignition amp, but what do I do now, try another one or just run without it?

Edited March 13, 2011 by unariciflocos

[jackherer 543]

You will have to post some pics and/or the part numbers from your ECU, coil etc. 1.9 Mi16 looms *all* need an ignition amp so either you have one somewhere you haven't found yet or you don't have a 1.9 Mi16 ECU/loom.

[unariciflocos 49 1 Cars]

There is no ignition amp on the loom or anywhere in or near the car.

 

Last two digits on the ECU are scraped off, but it's a 2 row Bosch Motronic unit, rectangular shape, rather than the square shaped ones I've seen on the 8 valves I've had.

 

The car is 30 Kms away but I'll take pictures over the weekend.

[jackherer 543]

Does it have one coil, five HT leads and a distributor cap on the inlet cam?

 

Also, does it have an airflow meter? If so it should be marked 0 280 202 202.

 

If it is the proper loom and ECU for an XU9J4 then the only way I can think of that it could run without an ignition amp would be for someone to have added some ignition drivers (large transistors) elsewhere to ground the coil. Inside the ECU case would be a possibility I suppose, does it look like it has been opened up?

[unariciflocos 49 1 Cars]

It does have one coil on the inlet manifold and a distributor and 5 leads. Everything looks as if it came like that from the factory.

 

Afm does end in 202, have 4 of them and the Ecu case didn't seem to have been opened. Will go by today and look closer and take some pictures.

Edited March 17, 2011 by unariciflocos

[unariciflocos 49 1 Cars]

ECU seems to have been tampered with. T500 seems to have been changed or resoldered at one time, B501 is missing and a bridge has been made in the second picture where the arrow is pointing.

 

I'll just leave it like this until I change to bodies and Megasquirt.

 

ECU is Bosch Motronic 261 200 11 and the last digit is scraped off, but I assume it's a 9, the one PeterT hasn't seen any of .

 

 

 

[jackherer 543]

Wow, that is actually very interesting. I was half joking when I suggested someone might have done that!

 

Useful to know there is a workable solution when the world supply of Bosch MTR01s run out.

 

Is that thermal damage between resistors 601 and 602? If it is I suppose it could have happened when you tried to run it with two ignition amps

 

Does anyone have a photo of an unmodified two row ECU? Would be interesting to compare the original T500.

[unariciflocos 49 1 Cars]

Well, took the car out today for a spin, short 40 km journey and everything works fine without the ign amp. Pulls really good, but didn't floor it as this is a freshly rebuild engine. I'll just leave it like this.

 

That itsn't damage between the resistors, just a bit of dirt. Tried calling the previous owner to ask about what has been done, but the number is no longer in use.

[jackherer 543]

If it works and its not burning the coil out then you can't go wrong really I don't think.

 

Can you post the part number on your coil please, just to confirm its a standard one.

[unariciflocos 49 1 Cars]

*rebuilt even!

 

I'm almost certain it's a standard coil, but i'll look for the p/n next week when i bring the car for its Mot. I'll use it as a daily driver over the summer if the fuel bills don't kill me.