Originally Posted by hrdtduck
I have a 1999 Continental that has a engine miss at nearly all speeds that I cannot get corrected. Not all the time, not all the same cylinder (apparently). Been to the dealer, everything tests out OK. they say the Bosch plugs were the wrong "brand". Had them changed to Autolite. New coil over's all around..still have the miss. Injectors are clean. Have not checked fuel pressure, but kinda think the dealership would have done that already. See this problem is pretty commonplace throughout all the Ford models the 4.6 COP engine was put in...I'm not satisfied with "we cannot find the problem". Can anyone help??
You say they replaced all the coils. Hopefully, even though new, none of them were defective. Did they look at the boot and wire that connects the coil to the plug to see if there is any arcing? I noticed this happening on my previously owned 99 CV. The solution for me was to thoroughly coat the inside and outside of the boot with silicone dielectric connector grease.
I also found that single platinum plugs ran better than the double platinum plugs. Double platinum plugs wear longer, but have higher resistance and therefore require more energy to fire.