Changed the plugs in my Dodge Ram Van 1500. I used Bosch Plat. Plugs, gap 04.5. I now have a miss. what is the next step in checking why I now have a miss
Thanks

 

First problem is the platinum plugs. Plain old spark plugs work better than platinums in a Dodge.

To locate the misfire, pull one plug wire at a time and listen for a drop in RPMs (about 50 rpms). When you find one that when pulled doesn't change the RPMs you've found the skipping cylinder.

 

Thank you problem solved.. will remember that about the plugs.