Vauxhall vectra 1.8 petrol injection. starts ok but when cold runs very poorly ,no exceloration until warm then a little slow to respond. had engine warning light once but no longer. ran new earth to heat sensor and air flow sensor much improved from origional prob when no power at all. had new coil pack last year changed plugs at wkend old ones black from excessive fuel. any ideas?
sounds very much like a cold start sensor or oxygen sensor, if the engine light has been on then it will store a trouble code on the ecu, take it to vauxhall and they will tell you within minutes what the trouble code is, Simple!
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