My 4-cyl 940 turbo, 259k, sputters for a moment and then shuts off after being cranked. When I press the gas pedal during this time, I could really tell that it is mis firing. After about three or four times of sputtering and shuting off, the problem goes away. My volvo mechanic has checked the entire fireing system, i.e. roter buttion,spark plugs and spark plug wires and replaced the fuel filter, but the problem persist. The first crank of the day does fine, but when I crank it for the second or third time of the day, is when the problem occurs. Could someone please tell me what to look for or check?