Have an '03 Max SE that just starting running rough.It idles a little rough and sputters and bucks when accelarates.I have 75K and never tuned up.I do the normal service and this just happened kind of suddenly.I will add a fuel addative for any gas issues,but i think it may be something else.Also the SES light was flashing on my way to work today,but did not stay on.Any thoughs?Thanks

At first I was thinking you may have a MAF issue but since you mentioned the Flashing CEL. That is indicative of a P0300-306 DTC which indicates a single or multiple cylinder missfire. The reason the light is flashing is to warn you that you are in danger of severe damage to you catalytic converters.

If you are going to do this without a getting it properly diagnosed I would start with plugs. NGK direct replacement only.

When pulling codes,it was a misfire and the MAF.It was easy for me to replace the MAF sensor,but I did have the rear coils changed.by process of elimination,none of the front ignition coils were bad,but one of the backs were.We did replace all three due to the wonderful access issues.That pretty much wrapped it up.Thanks Brian