I have a neon with around 125,000 miles on it. It sat for a few months an ran perfectly fine prior to it sitting. It was started periodically but not driven, then all a sudden it would not start anymore.

From trying to start it so many times the battery went dead so I charged it and nothing. I check for spark and nothing. I replaced the coil and no spark still. There were no codes then one time it showed a cam sensor code so I replaced the cam sensor and nothing. The fuel pump turns, it cranks fine, I swapped around some of the relays incase one went bad but nothing. I check the ground on the block its tight and appears to be intacted.

Could the PCM have gone bad?
Is there a ground for the PCM or is it grounded by the frame?

 

So after replacing the coil, then cam sensor, then PCM, I finally changed the Crank position sensor and it fire right up.

Luckly the guy I know at the junkyard will let me return the PCM that I tried.

I noticed on the crank sensor it was gunked up a little with oil and the metal cover would actually turn. I am hoping it was the sensors and not the pig tail but I guess I will find out once I start driving it.

 

If there is something in the pigtails, you can get contact cleaner and spray them out.

 

The connector was clean, I heard it was a common problem that the wires I guess would go bad because they are so close to the exhaust. They sell the pigtail at the parts store.