1.2 X12XE rough running

[ppl]

I have a 1.2 corsa with the x12xe engine which began running rough with limited pulling power - it sounds as though it's only running on three cylinders but cannot prove it as you cannot pull off a plug lead as you could in the "good old days"! There are no ecu lights and I checked this with Vaux check software which confirmed no codes, pending or actual. Have changed the plugs and air filter to no effect. Compression is only 80 psi on cylinders 2,3 and 4 compared to 120 on 1 but I doubt the head gasket as no water loss or signs of water in the oil (engine has done 80K miles). I suspect the coil assembly and am trying to "borrow" one locally before paying @ £60 for a new one which might not work. Anyone had a similar problem? All help appreciated. Dave

[nath2905]

you done the spark plug leads 2?
it struggling for petrol or over fueling?
cant be much else, unless it back fires and sh*t

[scoops]

describe the 'running rough'... is it a rough idle..does it do it at certain revs, does it do it you nail it, or even whn gently accellerating, any warning lights pop up on the dash?

[ppl]

You cannot check the plug leads as there aren't any - the coil pack clamps directly to the plugs.

I cannot determine whether too weak or too rich as the new plugs appear the correct colour so far.

The rough running is at all speeds - we used to say such an engine was "lumpy" and sounded as though one plug was down or the choke was partially out. The car accelerates and will run up to 60 (not been on a motorway as yet) but is not pulling as it should i.e. I need to take a hill in second gear instead of being able to take it in third as normal. You can feel the uneven running as a vibration at idle.

As I stated, there are no ecu alert lights and the temperature is normal.

I did notice after a 45 minute trip today, that the carpet on the "tunnel" between the seats was quite hot so maybe the baffles on the middle exhaust box have collapsed although it's not making any noise there?

Thanks,

[ppl]

For info' incase anone else has the same problem, I today received a coil pack, changed it and all is now o.k..
David