Missfire Problem

[Bowlerwell]

So, I went down to the car this morning to diagnose the problem...
What do you know... it's not doing it anymore...

I disconnected an injector lead anyway, and that told me that Missfire was definitely the problem before. What are the likely caises of an intermittent missfire?

Spark plugs?
Coil Pack?

Thanks.

JB

[BRY]

Most likely to be coil pack or the wiring to them.

[Bowlerwell]

Thanks BRY. I'll have to wait till the next time it plays up to find which cylinder it is.

Meanwhile, does anyone know the part numbers for coil pack, and the wiring between there and the spark plugs?

Thanks

[Jas11n]

My bro recently had this (95 ABY Coupe in kingfisher blue )
Initially it was intermittent, but then developed into a constant loss of one cylinder.
The cylinder in question was identified as per your other thread (removing injector leads sequentially) and then finally traced down to a failed POS (power output stage).
You have a one time fix for this as there are six (6) POS stages arranged in two sets of three.
Follow the information here for a "how to" on the POS stages. Could also be as you have suggested, a failed coilpack however.

[Bowlerwell]

Thanks Jas!

I found that the non-firing cylinder was the one closest to the rear...

The write-up at http://www.sjmautotechnik.com/troubl...4_Ignition.htm is very good, but it doesn't tell me where to locate the POS units... Where are they?

Are they arranged as shown in the above link, or are they oriented otherwise?
Can I do this job with them in position, or will I need to remove them first?

Thanks,

JohnB

[Jon441cc]

[Bowlerwell]

Thanks Jon!

Ok, I know that one of my P.O.S.s is broken now.
Missfire moved from Cyl 5 to Cyl 2.
I just need to figure out which P.O.S. that is, since ours aren't laid out like the S4 ANN.
Will order one tomorrow.

Does anyone know which is which? i.e. which P.O.S. controlls which cylinders?
Can anyone tell me what all the connecters just in front of the P.O.S.s are for?

THanks.

[Jon441cc]

Can anyone tell me what all the connecters just in front of the P.O.S.s are for?

THanks.

White connectors = power to coilpacks
Blue connector = Knock sensor
green connector = Knock sensor
grey connector = Speed sensor

i may be corrected

[Jon441cc]

Has anybody got a ABY overview ?

[AAH!]

I had the same problem and fixed it by rewiring the coilpack connectors and using the spare POS channel.

http://www.s2forum.com/forum/showthread.php?t=11198&highlight=pos