Ford KA, KA2, KA3 (1996 - 2008) - 99 1.3 Poor spark on 2 cylinders

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Thu 19 Mar 2009 09:21
99 1.3 Poor spark on 2 cylinders - skeeter
My KA lost power a few weeks ago and started running on 2 cylinders. Had the usual spark plug problem (now resolved) and have changed the spark plugs, leads and coil pack but I am still getting a poor spark on 1 and 4 whilst 2 and 3 are fine - which seems to imply the coil pack but I have changed that again to another brand new one and I still get the same problem.

Can't find any wiring issues so my final guess is that the ECU is somehow causing this problem - but wouldn't that mean no spark rather than a weak spark?

Any advice / ideas welcome!!!
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Thu 19 Mar 2009 14:43
99 1.3 Poor spark on 2 cylinders - piston power
I did hear of a similar problem with a focus they changed the coil packs twice but on the third go changed for a genuine ford unit this cleared the fault the same one your having.

Is yours a genuine ford brand new unit or a replacement part?

It seems the non genuine can't take the current and failed.
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Thu 19 Mar 2009 18:01
99 1.3 Poor spark on 2 cylinders - mfarrow
A faulty coil pack can cause damage to the ECU coil drivers - so this could be the problem. If it's a genuine item that's been fitted, and a compression test reveals nothing amiss mechanically, then I'd change the ECU or get it repaired.
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Mon 6 Apr 2009 15:31
99 1.3 Poor spark on 2 cylinders - skeeter
Thanks for the replies bigtee and mfarrow...

The coil pack was not genuine ford so that may be the case. Nothing amiss mechanically so I think the problem is either another faulty coil pack (although I do see 4 sparks albiet with 2 good sparks and 2 poor sparks so not a complete failure) or the ECU. I'm thinking ECU at the moment.

Does anyone know whats involved in changing the ECU on a 1999 KA? I have read lots of warning about key coding etc. but I'm not sure what applies to a 1999 (T reg) model and what applies to later models?

Current idea is to get another coil pack and a ECU and change both....

(ps. sorry for the delay replying - had PC problems as well!)
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Mon 6 Apr 2009 16:11
99 1.3 Poor spark on 2 cylinders - bell boy
cheapo coil packs dont always work from the box
i saw this first hand last week on a renault
how the heck something as simple as a faulty coil pack can be boxed up in hong kong fluey to be sold in a shop near you is unbelievable to me when a simple test could be done at the factory.
if new coil pack doesnt cure your ills and you need the ecu you will also need the key(s) for the reader on the steering downshaft and unless you are willing to swap the chip from one key to another you will also need to swap the ignition barrel (be aware the chip is glass and very easy to break rendering it useless if you break it removing it from the key)
obviously (as horse says) check wire and connecter continuity at the coil pack junction too
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Mon 6 Apr 2009 19:20
99 1.3 Poor spark on 2 cylinders - mfarrow
I suppose you could send the ECU off to someone like ECU Doctor or BBA if you can live without the car for a week or so. They should be able to test the ECU quite cheaply and repair if necessary.
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