J57ltr,
I'd agree that a faulty cam sensor would "usually" cause the car to be hard to start. To clarify, my car started without problems, idled fine, ran great... but at 5~7 lbs of boost would hesitate and backfire. All of this occured with no CEL. When I plugged in the Sunnen the code during the KOEO Running Memery test was 214.
Further, the CPS is never a "moot" point as the ECM algorythm uses input from the CPS at rates of up to 15,000 pulses per second. Operationally most ECM's (GM and Ford) read the CPS and CrnPS on a continious basis, regardless of whether or not the CPS produces a signal for the ECM's current-state computation. If the CPS is not providing updates, the ECM will not receive data to indicate how much timing to advance (for example) in the event of increased vacuum & rpm. The CPS provides a zero benchmark, the ECM adjusts timing according to the ZEROIZED signal from the CPS. The ECM (EEC) has absolutely no way of "knowing" where the cam and crank are in relation to one another OTHER than by a CPS and CrnPS. Some older ECM vehicles used only a CrnPS, but the exact time and delivery of the blow-mix was not as critical an issue as with a huffed engine.
I'd have to disagree that "it is very rare that the symptoms described correlate to a cam sensor." The symptoms described were those that I experienced, and the problem was the CPS. Not that rare when AutoZone, Kragen, and our local Ford dealer need to order the part (FMC parts advises me that they gobble up 3~4 a week). I think you'll find that a CPS is a component that is prone to failure. A number of posts alluded to the symptoms and corrective action(s) that have required plugs, wires, and/or a CPS.
I guess what I'm saying is that it could be MAF, O2, CPS, etc. The wires & plugs theory sounds like the Kragen auto guy that asks what year car you have when you need small block chevy rocker cover gaskets. It's not authoritative enough of an answer to to explain the performance degradation. Although, I have replaced wires & plugs and seen improvement, I have NEVER experienced such performance problems due solely to plugs and wires.
But I digress. I'd encourage all SC owners with problems to replace the plugs and wires. I'd also encourage you to swap the air in your tires, the coolant in the radiator, purchase stock in California's Municipal Bonds, and buy some property at the height of hurricane season in beautiful Punta Gorda, FL.
M Randolph
in SoCal somewhere in Kali~fornia
-95 Thunderbird SC/5-Spd
-69 GTO 400/T400
-67 Chevelle SS 396/4-Spd
-66 Nova SS 283/T350
-57 Ford Fairlane 2 Dr H/T 312 SC
-Searching for a 69/70 F/B Mustang