Computer problem
1999 Plymouth Voyager 6 cyl Front Wheel Drive Automatic

the van will not start without my OBD II scanner attached to it . I am curious as to why this is. Is the scanner bypassing something in the PCM to make it start. What should I be looking for and how do I fix it. Any help is much appreciated.

I had this happen to me on a ford vehicle .. took it to ford dealer to have the ECU read by them ? as you probably know OBD II readers have their limitations ? in laymans terms ford said the ECU had become clogged with info ? they cleared all faults and vehicle ran fine again ?? owner of vehicle was expecting to replace ECU/PCM ? after all a computer is a computer ?? hopefully yours could be the same situation ?