Engine Performance problem
1997 Volvo V40 4 cyl Two Wheel Drive Manual 88100 miles
i have a volvo v40 p reg 1.8i, i got a mate to change my spark plugs as i was busy. the car came back misfiring and he told me the ceramic from the spark plugs broke and fell in to the cylinder, it struggles with power and acceleration, where do i go from here? he ran the car before he gave it back, what do i do? please help i need it to run really well