Hi can anyone help out with a misfire on a ZX5 .... 2.0 l ...ztec .... automatic, only happens on acceleration around the 60 - 80 kms range most times it's just 3 or 4 quick little misfires then it's fine .... wires and plugs changed less than a year ago. 154000 kms on car. No check engine light, Any ideas ? Oxygen sensor maybe ? Thanks for any info.