Ok so I have owned my 96 dakota since 01 and it had been an absolute rock. Never have had a breakdown in the 153,000 miles ive had it. Frustrating that the paint job hasnt lasted as long as the truck so far but thats a topic for another day. But just the other day I had my check engine light come on so I went to the local parts store and checked what codes were showing up. Thinking I only had one I was rather suprized that I had 4 codes show up all at once. The codes I have is P0308, P0351, P0138 and P0141. From what I gather one is for the Ignition one is for the O2 sensor, one is showing that the number 8 clynder is misfireing and i cant remember what the other code is. My question is this. Is the O2 sensor causing a domino effect making all these codes to show up or is it somthing else. So far my truck is still running great so far so I'm more inclined to think it is the O2 sensor but I wanna check and make sure.

 

P0308 is Cylinder 8 misfire
P0351 Ignition Coil problem ("Peak primary circuit current not achieved with maximum dwell time.")
P0138 (Downstream) O2 shorted to voltage ("Downstream oxygen sensor input voltage maintained above the normal operating range.")
P0141 (Downstream) O2 heater problem ("Downstream oxygen sensor heating element circuit malfunction")

I've always been of the impression that the (downstream) post-catalytic converter O2 sensors were basically there to make sure the cat was still working (didn't make a difference to air/fuel ratio, etc). But, I'm not a Chrysler computer programmer/engineer.

I'd try to figure out if you are having a #8 misfire. Look at the distributor cap/rotor, wires, spark plug, etc. Inspect the wires running to the ignition coil, fuel injector, and the harness at the computer as well.