Check Engine Light / O2 Sensor

Twin coilpacks each serving two cylinders.   
Each coilpack ,sits on top of one cylinder with a lead to the other cylinder.

Hi everyone,

It's been a while and now seems like a good time to update this thread.

I had the 02 sensor replaced back in September. Since then the stalling issues I had at start up have completely disappeared - result!
However, now the engine shakes very slightly when idling, cold or warm. At cold, if I rev is up to 2,500 rpm or so I can clearly tell that it is misfiring but it's not throwing any codes. So I let it sit a minute from cold before driving and then it's very happy. Bit of a guessing game without any codes but I thought I'd replace my coil packs / ignition leads. (spark plugs were also replaced in September)

It's a 2002 TF 160 VVC and you can see an image of my coil packs on a previous post above. Now I know I have to unscrew the packs but I tried pulling the ignition leads out of their holes and they did not want to budge..at all. I put a fair amount of pressure on them and tried twisting them a bit but I don't want to break anything, so am I missing something? I thought you just pulled them out?

Also, I bought these ones http://mgmanialtd.com/index.php?id_product=1002&controller=product which I am very confident to be the right ones.
Currently, there are coil packs installed from Denso labelled NEC 100870. Scanning any MG website (rimmerbros for example) 100870 is not listed anywhere for ignition leads, not even as aftermarket, so could it be that a previous owner installed some slightly wrong ignition coils/leads?

Thanks as ever!

Oliver

They are the correct coilpacks.
The rubber connections often weld themselves to the plugs. I used some release spray down the plugholes.

Thanks David, that gave me the confidence to be a little more persuasive and I got them out, just waiting for the new ones and I'll see if that helps the issue at all.

I also read that faulty or worn crankcase ventilation hoses can cause rough idling / misfiring issues - does that seem likely? They seem cheap enough to give it a go, but looking on rimmerbros I have to buy ones depending on the engine number. I know where the engine number should be but it seems impossible to actually see it without taking things apart to get to it?

Is your engine number on your V5/registration document?

Not sure as I can't check mine for a few days. I did find it, however, stuck on the rear of the engine, on what I believe to be the timing gear cover. You can only see it if you look at it through the boot and best take a picture as it's hard to see from only one angle.

So all is good - I've got all the parts I need to mess about a bit and I will update if I manage to fix the poor idling, misfire at cold.