hi everyone new to this board bought a 2003 golf gti 1.8 turbo ran fine to today started to skip and head not much power went and got 4 nwe spark plugs and head them download ed ,,,. says cat alyst efficiency below threshold and no 3 missfife detected so we changed all plugs and fixed broken air pump hose to vavle cover ( gos back toweds the turbo) dis conectd the battery to reset cumpeter , but still skips so checked spark goineg to no 3 and got no spark ,,,is this a cumpeter problem or a electeal problem why are we not geting spark to no 3 ?????

 

First welcome! Second, could be the ignition coil, they go bad, plug wire could be bad. That's all I know.