Q&A

 Master

It could be many things, unfortunately and without experiencing the problem first hand or being able to do some basic diagnostic tests its hard to say. Is the Check Engine Light on? if so codes stored in the computer of your car will indicate where the problem is, but a scan tool is required to retrieve codes stored. On the 4cylinder you could have sensors in the distributor going bad or any number of problems, V6 engine uses individual coils per cylinder, again too many possibilities just to guess at the problem.