corsa lacking power, emmisions light flashing

[dawze]

hi i have a 51 plate 1.2 16v corsa club. a few days ago now my car started juddering when pulling off and not being responsive when i accelerate then suddenly will shoot off. my emmisons light was already on before this, it is because the cat is nearing the end of its life but when i pull off and the car judders and isnt responsive on the accelerator the emissions light will start flashing and then stop after a few seconds. i have the following error codes:

P0300 Misfire Unidentified Cylinder Detected B-21
P0301 Cylinder 1 Misfire Detected B-22
P1613 Immobiliser No Or Wrong Signal Immobiliser C-05
P0420 Catalyst Efficiency Above Threshold C-31

when i first turn the engine on and start driving there wont be a problem it will start after a few minutes. does anyone have an idea what my problem could be? thanks in advance!

 

[leewill]

i would change the cat and the oxy sensor,

 

[andyandy2]

I would suspect the coil pack(s) not sure if they are linked or seperate on the 1.2 engine they are situated on the top of the spark plugs.

Don't waste money on cat or oxy sensor, until you've tried the coil packs, the codes are telling you you've got a cylinder misfire, the vauxhall warning light works in two stages, if the light comes on and stays on it means a fault is logged, if it continualy flashes t means a fault is logged which can cause damage to the catalytic convertor, (i.e. overfuelling) a flashing light needs immediate attention ( to save extra expense)

 

[newtzy]

try the lamba sensor could be bringing in the rong air mixture

 

[jonnyfishing]

I think you should go for the coils as "andyandy2" has suggested, cheapest
and from the codes it is indicating, one is bringing in the others.

 

[jetex]

First of all, remove and check your spark plugs. Check that they are all the same colour, or better still, replace them. The next step is to check the cylinder compressions. They'll probably be o/k, so the next step will be the coil pack. There are obviously other checks that can be carried out before replacing this (oscilloscope checks etc.), but from experience, it will almost certainly be the coil pack. The E.C.U will show a Lambda sensor fault code because petrol is going into one cylinder, not being burnt, and coming straight out the exhaust, putting the sensor outside it's parameters. The other codes are spurious, and are being caused by the main reason for the misfire.