I have a 2000 Durango with an engine miss that just wont quit no matter what I do about it! I can be driving down the road and the engine will just start missing. The tach doesn't jerk at the same time the engine misses, it is about 1-3 seconds after. The 'check engine' light is on and it is p1391. If anyone has any ideas, let me know!

 

There isn't a p1391 did you mean p0391? if so here's the code
P0139 O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)

That is in the 1st gen section under the engine code index
https://dodgeforum.com/m_614377/tm.htm

I don't know how likely that is to cause the engine stumbling but it's worth a shot. Change out your o2 sensors and also run some sea foam through the gas tank and the brake booster lines. Clean up the TB. If you haven't tuned it up in a while now is probably the time. One more thing don't cross your wiring when changing the ignition system out and use OEM or MSD. If you have platinums get rid of them and run champions... Let us know how everything works out and one more tip, not many people check this area you should go to 1st gen to ask your questions. You will get a lot more hits.