'02 Saturn SL2 1.9 SOHC cam position sensor code

I am currently working on an '02 Saturn SL2 with a SOHC 1.9l engine. The car has about 60k miles on it and is in very good condition. The engine seems to run flawlessly. The check engine light has been on for at least a year or more, I don't know for sure how long because it's my friends car and he bought it with the light on. I understand that the SOHC version of this car has no cam sensor but uses the ignition pulses to determine cam position. I have done a lot of research on this issue and have replaced all of the ignition system(with new saturn branded ac-delco parts). I have also went through the harness wires and grounds, thinking there may be a short or corrosion, however neither of those was found to be an issue. I bought a used ECM from ebay for the year/make/model/transmission but none of the dealerships will reprobram it b/c it is too old. The only option for reprogramming is mult-hundreds of dollars and you would have to send the computer out via the mail. All in all this problem has me stumped. My friend is livid since he spent all his available money on parts I recommended to him, and I have not solved the problem. I feel like an asshole, but I am just going with the information I have. As of now, the problem still persists- The check engine light comes right back on within a few minutes of clearing the code. The cam position sensor code is the only code that comes up, nothing else. I have scanned it with 2 of my scanners and have had it scanned at a local shop as well, all could only see one code- the camshaft position sensor code. My friend needs to get his car inspected(in NY) and is not able to until this code is gone. Is there anything else I have missed. All the info online says it is one of the things I have already replaced, so if it's not one of those things, what else could it be? The only thing I can think of is the computer and replacing that comes with it's own set of issues. And, as I stated earlier the car runs flawless- no perceptible misfires or stumbling, plenty of power, good fuel economy, etc. I am at a loss. Please help.