galaxy misfire

[dashepster]

My 2000 ford galaxy has suddenly stopped firing on cylinders 1 and 3 without warning, fuel is OK but no spark, cylinders 2 and 4 are fine which means both coil packs have gone down at the same time which to me seems strange, so my question is... What else can stop cylinders 1 and 3 from sparking considering 2 and 4 are running fine. Please help as I use my car everyday for school runs and work and need it back on the road ASAP. Any advice is welcome.

[dashepster]

I also forgot to mention that I have tried new spark plugs and tested the old spark plugs to which all plugs work perfectly, so it must be somewhere between the coils and the ecu.

[insanitybeard]

Have you got the setup with a single coil pack for all four cylinders at the end of the cylinder head or the two separate ones that sit underneath the cover inbetween the camshafts on the rocker cover? (from your first post I'm assuming it's the latter)

[dashepster]

It's the twin coil pack, coil pack 1sits above cylinder 2 with ht lead to cylinder 3 and coil pack 2 sits above cylinder 4 with ht lead to cylinder 1.each coil pack has a single 2 point input plug and 2 outputs, 1 via a stem that goes straight down to the spark plug and 1 via ht lead.

[insanitybeard]

I'm familiar with the setup, it does seem odd that it's simultaneously affected both coil packs, especially as from my understanding of it each coil pack should fire both of it's spark plugs at the same time (wasted spark). Before going too far looking for wiring faults I'd see if you can get a couple of substitute coil packs and/or HT leads to try and 100% eliminate as the fault, as the cylinders affected are the ones connected to the coil packs by the HT leads (instead of the direct connection from the coil to the plug) it is possible the insulation has broken down on the HT leads, though I'd expect that particular defect to cause a misfire, not complete loss of spark on the affected cylinders, therefore I'd be thinking coils first. If required, the leads should be available as separate items from Ford- this parts diagram is for a Transit (which also used the 2.3 DOHC engine in the rare petrol version!) but should give you an idea, don't trust the quoted part numbers as gospel though.

Regarding ignition faults, the usual suspects for failure are the plugs, leads and coil packs so I'd want to be 100% sure they're not the cause before delving deeper looking for wiring/ ECU faults.

[dashepster]

Thanks for that insanitybeard, I've ordered new coil packs hoping that this is the fault, I have just found that one of the coil packs (coil pack 2 cylinder 4 - 1) has a very small split in it, I only noticed because it was going dark and I could see a spark from coil pack to cylinder head and everytime this briefly stops no1 spark plug works, so coil pack 2 is definitely faulty.