Ok... We can start with the basics. Disconnect the battery first.
1. disconnect the coil pack, unbolt and pull out the coil pack unit .
There must be some residual oil down the spark plug well so what we need to do is to get as much oil out as possible and make it sqweaky clean.
2. Inspect the long rubber boots that attaches to the top of the spark plugs. Make sure that there are no splits in the rubber or chunks missing. If so , it needs replacing....Coil packs are fairly generic or standard which means that you can get a decent one from a breakers yard from a similar twinspark (any cylinder number will do 1, 2, 3 or 4, just make a note of your current part number) if it is damaged and swap it over. Usually expect to pay about £10 at a breakers yard.
Yes... you can remove them from the metal rail and replace only one pack if needed.
Any splits or chunks missing in the rubber boots then the coil pack with simply ark to the cylinder head instead of making contact with the spark plug, thus causing a misfire... Oil won't help as it conducts the spark even better away from the spark plug... Thats why it's so important to clean any tiny bits of oil off the parts above... Oil also has an effect on the rubber boot too making it weak, soft and slimy and easy to split earlier than it normaly would. It looses its non-conductive properties.
If the rubber boot is ok and in good condition, make sure that there is no oil around the inside of it.... Using a tin of brake and clutch cleaner and some cotton buds helps a lot here.
3. Now remove the spark plug, one at a time, 8 in all
and inspect it... if it is wet with petrol then their is your culprit, it should have a dry light sooty coating at worst and once you rub it lightly with your finger you should see a light grey/ brown tinge on the electrode
If its wet with fuel, give it a quick dry off and use a light wire brush to clean off any residue, let it dry out for a few minutes.
4. Dont worry too much about any remaining oil dropping down the threads of the spark plug hole, it will burn off when you first start the car after you are finished. Lightly dampen a clean rag with the brake/ clutch cleaner and give the spark plug well and the spark plug threads in the cylinder head a good clean... a long piece of cane with the rag wrapped round the end helps a lot, like a bigger cotton bud.
5. Re-fit the spark plug but dont over tighten it... Nip it up and then give another quarter turn with a ratchet bar and socket.
Now refit your cleaned off coil pack bolt it down and reconnect it...
6. Now do the same to the rest of them for good measure one at a time
& like I mentioned in my earlier reply, check the connections to the Fuel injectors it can give a similareffect to a misfire if one is loose These are red in colour and sit at the back of the rocker cover, 4 in all... Disconnect each one at a time and refit securely
I have included a link to a very good member's site that will help you with the 2.0 TS basics
Gazza82's Alfa 156 2-litre Twinspark
Look under the heading of Hint's and tips
and click on the link for 16v spark plugs
... All what I have explained above is there and has some pictures if you are in doubt mate ok.
Once you have done all this, then reconnect the battery, and hopefully it will be no longer misfiring...
Then you can perform the ecu and throttle reset proceedure at the same time
in this link http://www.alfaowner.com/Forum/alfa-...acle-cure.html
Just To make sure you have got rid of old ECU values and you should be ok. That is, if nothing else is causing your issue.
Thank's to Gazza82 for a very good website BTW