1996 Mercury Villager • 163,000 miles

Complete tune up was done. Cat was replaced and I still have misfire on cyliner 2. Cylinder 2 injector was electricly confirmed as working. Compresion of cylinder 2 at was at 63. Cylinder 3 at 80, cyl 5 at 100. I'm tempted to replace the injector because similar rough take off was experienced in other villager with misfier on cylinder 5.
February 3, 2013.

The injector isn't the problem. Based on the compression in that cylinder, it sounds like you have internal engine problems. Compression between cylinders should not be more than a 20% difference. Also, 63 lbs of compression is very low. So is the 80. You may have a blown head gasket or internal damage such as worn rings, a burnt valve, or a sticking valve.

Let me know if you have other questions.