156 2.0 ts - Alfa Romeo Forum
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156 2.0 ts

Can the computer from a 156 2.0 TS be tested for malfunctions? If so, are they a repairable item? Or are they a "throw-way" item needing to be replaced wholly?

Is it possible to simply unplug the existing computer, remove it, and then plug in a good replacement without the need to have anything re-programmed? That is, a sort of 'plug in and play' item.

I have discovered that all four spark plugs are firing at the same time, yet I have installed a brand new crank sensor and cam sensor. I also have the timing set up properly - at least from a mechanical point of view. Everything else seems in order. My conclusion is that the fault must lie somewhere in the bowels of the computer! Is this fair thinking?
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Have you tried plugging the car into diagnostics? Multiecuscan is free and a set of cables can be had for under £20, that will give you a better idea of what's going on.

As for ECU's yes, they can be replaced. You can pick one up from a scrappy but you'll need the locks, keys etc from the donor car, or, you can buy a vitginalised untit which I believe is plug and play, but I may be mistaken.
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Quote:
Originally Posted by alfanut2day View Post
I have discovered that all four spark plugs are firing at the same time...
You know you have eight spark-plugs...?

Quote:
Originally Posted by alfanut2day View Post
I also have the timing set up properly - at least from a mechanical point of view.
Did you use the correct engine specific cam locks and a dial gauge to accurately find TDC?
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Quote:
Originally Posted by alfanut2day View Post
I have discovered that all four spark plugs are firing at the same time
The Cylinders run in pairs 1 / 3 and 2 / 4.
http://i1.ytimg.com/vi/bF6ohEIu85s/maxresdefault.jpg
This configuration is for wasted spark - meaning that at when Cyl 1 fire for ignition, Cyl 3 fire exhaust stroke to make sure all gasses are burnt - it help with emissions.

http://www.alfaworkshop.co.uk/images/25-1-800.jpg
This configuration is pure twinspark in the sense that both sparkplugs fire simultaneously in one cylinder - bigger bang

I need confirmation on this: AFAIK the ECU fires at both compression and exhaust strokes - in both cases you get twinspark at both strokes - best of both worlds

The benefit with the longer leads are that if one coil pack packs up you still get spark from the other coil pack you only loose the twinspark in 2 cylinders
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Most cars operate on the wasted spark system.
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Firing 1+4 & 2+3 was on earlier models ... I have that config on my '98 (first pic maxresdefault)

later they went to the 1+1, 2+2s in your second picture (25-1-800)
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