Long story short. Recently replaced all plugs and put on a new muffler. Last night while driving truck died. Pulled to side of road to try and start it. Turned ignition and it spat and sputtered and didn't want to stay running. I gave it a little gas and it seemed to want to stay running but it just spat and sputtered some more and died. While spitting and sputtering I noticed the interior light acting up to, they would dim out and go back to normal. I tried this a few more times with the same result. Got it towed home and now this morning it just won't start. I can turn the ignition and it feels strong like it wants to start but it just won't catch. I checked all of the wires and fuses and relays. Any ideas? Fuel pump? Filter? O2 censor?

 

No check engine light? You might want to check your plugs and wires to make sure everything you touched is in good shape. But it sounds a lot like a crank position sensor, although it could be several other things too.

 

Check for codes, not everything trips the CEL.

With the truck not running, turn the key to RUN (don't start it), then OFF, back to RUN, then OFF, then leave it in RUN.

Codes will display in the odometer. It will say P DONE when complete.

Many of your symptoms would also fit a bad battery. Dakota's don't run well when it is even slightly weak. You might want to get it load tested.

If it tests OK, check the fuel pressure. You can rent/borrow a fuel pressure gauge from most part stores.

 

Maybe go back and check the plugs, be sure they are all gapped correctly. You did not say if you replaced the wires, distributor cap and rotor but check those too. Any one or a combination of those could be the cause of the problem. Check the battery voltage and alternator output with a volt meter. It should be 12.6 volts with the ignition off, with engine running but no accessories on you should have about 13.5 to 14.5 volts. Then turn on the high beams and AC with the fan on high speed. The voltage may drop a bit but if the alternator is OK the voltage should come back up around 13.5 to 14 volts. The best way to test the battery itself is remove it and take it to a good auto parts store to have it load tested. Like Dan pointed out Dakota's are very sensitive to low battery voltage. You can have serious problems even at 12.0 or 12.1 volts on the battery. Parts stores can also test the alternator whether in or out of the truck but the best way is with it removed from the truck.

If the battery, alternator and everything else check out OK you may need to look at the Crankshaft Position Sensor. I recently had a problem with my own truck cutting off while driving and it turned out I had a bad crankshaft position sensor. Usually when the crankshaft sensor goes bad, the sensor gets hot and the engine will cut off and not run until the truck sits off for a while so the sensor can cool off. Then it will crank right up and runs OK until the sensor gets too hot again and the engine shuts off. I am not saying for sure you have a problem with your crank sensor, but it might be bad if everything else checks out OK.

Check for codes. When my crank sensor went bad it set a P1296 code for low voltage to the Manifold Absolute Pressure sensor. There is a good thread here about crank sensors, another member gave me some great help on mine:

https://dodgeforum.com/forum/2nd-gen...ling-coil.html

Jimmy