'95 Jetta 2.0 check engine light, no codes

I tried the search engine but didn't come up with anything. I have a '95 2.0l Jetta with the check engine light on. I have the jumper tool under the seat. When I follow the procedure for using it like is outlined here and in my bentley manual all it does is shut the light off, it never flashes a code. Then as soon as I start the car the light comes back on. I do not have the cables or software to hook up to this car with a scan tool. I think the I might not get anything if I did being how I cant even get anything with the jumper method. Has anyone on here run into this and what do you do about this. This is going to be difficult to figure out if the computer wont give me a place to start. Maintenance history, had a tune up recently, checked the plug at the distributor, cleaned the mass air flow sensor, there is some oil in the rubber intake. I checked the O2 sensor and it is working fine. If anyone on here has any advice other than "I don't know, take it to a mechanic", please share it. I am an ASE certified master technician with advanced level certification. I own a car repair business, however, this is my personal car and I don't specialize in European cars. I have an OTC Genesis but I don't have a cable that will plug into the diagnostic port on the car. Actualy, the OBDII cable will plug into it but it wont communicate with the car, the car is not OBDII. I also have another '95 Jetta 2.0 and just for the fun of it I tryed to get the check engine to flash on it but it does the same thing as the other car. So, how the hell are you supposed to get codes out of these cars if you don't have a VW scanner??! Thanks in advance for your help.

man this is a slow forum! well I took the car to a friends shop, he has a snap-on scan tool that will plug into it. The trouble code is 00515 Hall effect sensor, open/short to power or ground. So I guess I will check the inputs into the distributor, have a look inside it to see it there is anything obviously wrong that can be fixed and if that doesn't come up with anything than its time for a new distributor, or a junk yard one. Automotive forums has been a huge help to me in the past, thanks everyone. I will post again to let everyone know what the problem ended up being. The symptoms other than the check engine light is a slightly extended crank time, kinda funny idle (it hangs high sometimes for a moment) and a somewhat flat spot between 3k and 4k rpms

update:
checked for voltage between the two outer terminals on the distributor plug, there is 5 volts. l see that there has been a couple posts on different boards where people thought that you should have at least 10 volts between these terminals. My bently manual says that on the 4 cyl you should have at least 5 volts and on the 6 cyl you should have at least 10 volts. Being that this is a 4 cyl car, I assume that the voltage I have is correct. I checked for continuity between the two outer terminals on the distributor and there was none. I took this to mean that I need a new distributor so I swapped it out with one that was in another car that I know has no problems. Cleared the code and after the second start the light came back on, same code. So, I guess that the distributor was fine. I didn't have any more time to mess around with it and wont till the weekend. I have heard that having the timing off can throw that code. The timing belt was replaced by another shop shortly before I bought the car. I guess I will put #1 cyl at tdc compression and see if the rotor is pointing at terminal #1 on the cap. This will tell me whether they lined the marks up right on the intermediate shaft when the replaced the timing belt.

I'm currently going through the same problem. Have you been able to solve the problem? I have put in two new distributors and the check engine light will still come on after a few days. It has to be a wiring problem as the signal is only intermittent. I hope to get a better idea on this before I take it to another shop.

Thank you for the help and I hope to hear we both have some success.

Doing some further reading, it maybe as simple as an ECU. At least I have some ideas to try it before and when I do take it to a mechanic, again.

I found an earlier thread and their problem was caused by a pinched wire going to the distributer. Hall effect sensors are used to determine position. I'm not sure if only the distributer has one on your car. They are often used for cam shaft sensors. Check to make sure all your sensors are properly spaced and non of their wires have been shorted out. Also make sure none have come unplugged.

I do think there was some sort of problem with the engine light just coming on for no reason and the car was working fine it could be just that simple of a problem.