P1383 OBD2 Code Repeated After Timing Belt Replacement: 20XX VETECH 2.0L DOHC Engine at 215,000 Miles

I purchased this vehicle in July of last year and have not yet reached its first anniversary. Despite only two timing belt replacements (first in October, second in January), the P1383 OBD2 fault code has appeared five times. This is highly unusual—timing belts typically don't fail so frequently or repeatedly. The vehicle is a 20XX VETECH 2.0L DOHC engine with approximately 215,000 miles. I performed routine oil changes and used Seafoam (only 1/4 solution for about 30 minutes) to clean the system, but after that, the car ran roughly. When I started it again, the Check Engine Light illuminated, and the P1383 code was triggered. I replaced the spark plugs a month ago—should I replace them again? If not, what other components could be causing this issue? I currently have five vehicles at home, and it seems that two are always out of commission. It would be ideal if all of them ran simultaneously. I also wonder: can modern cars really last 50 years without major issues? I believe they can—but manufacturers don’t seem to prioritize longevity. Additional details: After the October timing belt and tensioner replacement, the engine developed a slight misfire. Following the January rebuild (including seals), performance deteriorated significantly. I took it to a Ford dealer who claimed the timing was improperly set and corrected it. However, after changing the oil yesterday, the car ran roughly again—P1383 reappeared. I know P1383 is often associated with issues like the Crankshaft Position Sensor (CMP) or Variable Cam Timing (VCT), but I'm having difficulty locating these components on this model. The diagram I have indicates the CMP should be near the air intake resonator—but I can't find it there. Additionally, during a previous timing belt service, a wire was left unconnected behind the firewall near the steering pump. It runs in a loop to the timing cover and appears to be an electrical ground. I pointed this out to the mechanic, who admitted they missed it. After reconnecting it, the idle became rougher and misfiring worsened. I also want to confirm: is VCT the same as the PCM? And where exactly are the CMP and VCT located? This situation has become extremely frustrating—costly, repetitive, and difficult to resolve. I'm seeking reliable advice on what could be causing this persistent P1383 code and how to properly diagnose it without repeated repairs or unnecessary part replacements.