I currently drive a 2000 Excursion with a 7.3 Powerstroke. It has some mods done as listed in my sig.. I replaced the old (non black but grey) CPS with a new updated version from Ford, when I installed my melling lpop.
The truck has always had a slight miss at idle.
I checked the Perdel % of the new CPS (from Ford) and it was 3.5% on cylinder #4 and 6.2% on cylinder #8.
Still had the same miss at idle.
So I decided to get the Echlin brand NAPA CPS. It looks identical to the original black CPS from Ford, but of course its not the same part.
I was amazed. Perdel % is only 0.5% on cylinder #4 and 2.8-3.0% on cylinder #8.
The truck runs much smoother and no miss at idle. Also it feels like the truck is lighter at highway speeds (more response at light throttle).
All the observations where done on a snap-on modis.
I want to mention however, that I am not saying one is better than the other. I just like the Echlin better with the current mods I have done to my truck. I also carry a spare in the truck at all times.
The price on the NAPA CPS was roughly $20 and part #CSS1103.
I finally fixed the annoying miss at idle!!!