i have a 2001 ram with a 5.2 and a 5 spd. In the summer it doesnt really happen, but in the winter or cold rainy days it wont start. ive changed fuel pump, crank sensor, cap, plugs and wires. It turns over fine like its going to start, but never does. It will chug once or twice and go right back to turning over...andybody have any info on this please!!!!! Everytime it wont start i have it towed to the dealer and it freaking starts in there parking lot.....So they can never find anything wrong with it..

 

Coil.

 

when it won't start, do you have spark at the spark plugs ? this will point you to electrical or fuel...

if electrical, there's coil, cam position sensor inside dist.

if fuel, there TPS, IAC, injectors, pump.