I have a 98 Dakota 4x4 with the 3.9. It has been throwing a p0351 code, and was throwing a crank sensor code as well. It was running rough, having a hard idle, spitting/bogging, etc. replaced the crank sensor, made it better, smoother idle, ran a little stronger, but woul;d still occasionally buck/spit/miss, and the p0351 code was still there. so i replaced the ignition coil, and it seemed to help at first, ran stronger, smoother, etc. but then i realised that in the morning, on cold starts, or any other time the motor was cold, it would fire up just fine, then after about a minute, it would just die, like i shut off the key. sometimes it would fire back up after a minute, sometimes it would take as long as 5-10 minutes before it would finally spit and sputter back to life. the whole time its refusing to refire, i can smell gas, but then once it finally does refire, it seems to run just fine, im kind of thinking that maybe my new coil is actually defective, because it would never just cut out before this new coil, but idk for sure, should i try a full tune up first? or does anyone have any input? im at a bit of a loss here, and i work as a delivery driver, so this really needs to be fixed asap, thanks for the input.

P0351 Ignition Coil A Primary/Secondary Circuit Malfunction

 

Not sure what the code is but have you tried changing 02 sensors?

 

Added code definition, throws a secondary 02 code, but i have no cats, so i figured thats why.

 

so the crank sensor code cam back today as well, im thinking its an ecu problem, anyone else have any opinions?

 

After about 120K miles you should start replacing all your sensors anyway its a must if you want a good running smooth idling engine.

MAP, TPS, O2 up and down's oxygen temp sensor clean out the TB new IAC if needed and crank sensor I forgot the coolant temp sensor and thermostat also then check and replace all vacum lines as the hoses will be getting hard and brittle.

Keep all your old sensors as a backup.

Check your CAT and muffler if never replaced they may be clogged/bad.

 

Hey guys, new to the forum. Upon reading your post i felt compelled to register and reply. Being a former Dodge/Chrysler/Jeep tech I've seen the code you're referring to frequently caused by PCM failure. Its a notable common thing with the Jtec pcm. Not saying thats your problem for sure, but If it were my truck that would be my prime suspect. Try tapping on the PCM with the handle of a hammer or heating the pcm with a blow drier and see if the problem is easily duplicated if you want some more assurance...

 

Seems to certainly be the exult, what's a good place to get one on the cheap?

 

NOT Autozone lol. I work there and am having an issue with the PCM in my truck. My truck runs fine but as the PCM warms up....say in a drive thru mid afternoon, it will stall, and if driving it will hiccup harshly and the check engine light will flash during the occurance but not stay on or store any code, the PCM loses power internally ive found.
Anyways, We sell Cardone PCMs. I ordered one, got it two days later, installed it, and the truck wont even start. Tried everything. Even when I was a tech, Ive never ran into a Cardone PCM that worked properly but ONCE on a towncar...

 

I am having the same problem with mine right now. It started with a bad ignition coil which I replaced. Fixed it for a while then It started to die intermittently when driving, mostly when I went to put it in reverse. It would start right back up so I replaced the crankshaft sensor. Help for a bit but eventually started to die at random again. After that I changed the pickup coil, distributor, spark plugs, wires, upstream O2, IAC, and TPS. I also had to buy a new cat and repair an upper plenum gasket. After replacing all this stuff I am still getting a code for ignition coil. I kept driving with it like this just putting up with it until I could see a mechanic but while I kept driving it I noticed a jumpy idle. It has always been a little off but now is even worse than before. I took a look at my cat and it was completely dark. I checked my exhaust and the bolts that hold the heat shield have snapped off flush and the heatshield was just sitting there. After I repair the leaky intake and snapped bolts I will be back to the initial problem with just the ignition coil. While driving it if I go over 60 it will backfire and want to stall. Same thing happens when driving in town but without the backfire. I am going to replace the muffler and cat again as soon as I can. Im guessing my O2 was bad which made my cat go bad. I just need to replace the downstream one now.

Specs:98 Dodge Dakota 3.9 A/T
Codes I am currently getting:

P0545-?
P0351- bad coil/pcm or possibly wiring. Swapped relays did nothing
P0420- bad cat

 

The 0545 is related to the AC compressor clutch relay.

dying in reverse is 100% crank trigger. Backfiring is fuel sync or improper ignition timing.