5... then 4....then 3 ! ! !

[JamesHarrold]

Hi guys....got a bit of a problem with my ABY

Dropped onto 4 cylinders yesterday whilst driving very conservatively around town, then this morning went onto 3 and would barely run, just managed to get home.

I checked and replaced the plugs this morning - No change.

With the engine running (just) I whipped the injector leads off one at a time to see if i could narrow it down to which cylinder(s) was giving me the problem. Number 2 seemed to make no difference at all when removed.
Is this pointing to coil packs - or injectors? and is it just me or is it odd for 2 to fail at once?

Any help would be much appreciated, just dont trust garages with my new baby, going from past experiences.

[Bowlerwell]

Is it an ABY?
You have 2 Power Output Stages. Each has 3 channels (therefore one is unused). Perhaps one of the units has gone pop, making more than one cylinder fail.
Try swapping them over. If you see the misfire move cylinders, that suggests a POS problem.
They are mounted at the top of the bulkhead in the engine bay. There are pics kicking about the forum.

[merlin's S4]

Could be a POS as you've had two go down at the same time. Try swapping the connectors on the two POSs around and see if the non firing cylinders move.

[Bowlerwell]

Ah. Thanks SO much Merlin for not putting an apostrophe on POSs!!

[Rusty]

POS's

[JamesHarrold]

Thanks for the advice guys....
But just tried swapping the connectors on the POS and it just pops and bangs and doesnt starts at all!
Any more suggestions?

[merlin's S4]

Thanks for the advice guys....
But just tried swapping the connectors on the POS and it just pops and bangs and doesnt starts at all!
Any more suggestions?

So does it start with the connectors in the original position but not when you swap them?

[JamesHarrold]

Yep... It starts on 4 when in the original position, but when I swap them it just pops and bangs and wont fire up.
Do you think it points to the POS, if not what else could it be?
James

[merlin's S4]

I would suggest it probably is a POS as swapping them makes it worse. Is there anyone with an S2/S4/S6 nearby that you can meet up with and swap POSs? I have a spare working set that I could send up for you to test it.

[andyg plym]

I would suggest it probably is a POS as swapping them makes it worse. Is there anyone with an S2/S4/S6 nearby that you can meet up with and swap POSs? I have a spare working set that I could send up for you to test it.

beet yoy to it

[DJones]

From the sound of it your just swapping one plug per POS you need to swap both i.e. keeping the two plugs that are on the same POS still in line once the POS is swapped.

The reason it's pooping and banging is it is firing in the wrong order.

Hope that makes sense....

[Bowlerwell]

Think that's the problem DJones.

Swapping only the outputs, or only the inputs will just give the wrong firing order.
Both outputs and inputs need to be swapped.

[JamesHarrold]

Oh....

will try swapping both tommorrow and let you know what happens.
thought it was a bit strange.

[Jas11n]

>>> LINKY

Info is for the AAN, but it's the same system, just the power output stages are mounted slightly different.

[JamesHarrold]

Thanks Jas11n
The link will be very useful.....gonna try again this afternoon.
Cheers guys
James