Since this is a chain of events issue, I wasn't able to find it searching.

The truck is a 97 1500 with a 5.9. About 8 months ago. I replaced the cam and crank sensors and distributor (long story), as well as the normal tune up parts. Since then, I've been chasing an issue which started as a cam sensor code, then it led to the truck dying and miss fires. Since then, I've replaced the cam and crank sensors again (the last time with factory parts), and the wires again (under warranty) and as of now I have it down to a miss fire, and stumbling when I let off the throttle, the miss fire’s are on 4 and 8. I pulled those plugs and didn't see any thing out of the norm, but thinking about putting a new set in any way. The current set is NGK. I've been doing a lot of reading hear about how people like the Autolights #3923. I just bought a set and am about to put them in.

Any one have any thoughts, or am I even looking at the right thing. When it was dying, it was throwing NO codes. That's when I replace the cam and crank sensors with factory parts. Then it started the miss fire thing. I had it at a local shop and with there computer they could find nothing. All he can confirm is it's definitely a spark issue.

 

Bad coil maybe, but I'll go with this problem for now. It at least needs to be confirmed either way. https://dodgeforum.com/forum/2nd-gen...um-thread.html

 

The coil is my next step, but plugs are cheaper. Those two things are about the only items I haven't replaced yet. The coil however was not involved in the chain of events leading up to this. It's also an MSD coil, it's a few years old though.

 

Didja get your fuel sync set up properly after the distributor swap?

 

Fuel sync what???? Never heard of that. Fill me in.

 

zman, I noticed the link you had put in about the blown plenum gasket. That's actually where this all started. last January I replaced the plenum gasket and cover with a nice kit from Huges. From looking at this forum, I read that it would be a good idea to do a tune up too, since you can't see the distributor with the intake installed. When I saw the distributor that was in it, the guy before me broke the passenger side screw for the cap, and had it held together with zip ties and permatex. I was borrowing a buddies garage, WHILE his 55 Chevy was sitting out side in an ice storm. It was Saturday night. The ONLY place that could get me a new distributor including cam sensor, was Advanced. I've been chasing problems since.

 

Well, you might need to take a good hard look at the dizzy cap and cam sensor!

 

+1 on fuel synch. Since you asked, I believe I can safely assume that you did not have this done, and therefore, this is most likely the source of your problem. On these engines, you do NOT turn the distributor to set timing. Turning the distributor changes the position of the cam sensor (inside the disty) and therefore, alters the fuel synch. It takes a computer connected to the OBDII port, engine running, to set fuel synch. Simplified, unless you have such a comouter available, you will need to take it to dealer or a shop that has one (and knows how to set this) to have it done. Pretty simple, only takes a few minutes.

 

No, we didn't know or set any thing like that. Would this kill the spark?

 

Score one for the hippie! (That'd be me.)

Tailgate101: Amplifying what gdstock has said, moving the distributor alters the fuel injector timing, and the symptom you've described sounds an awful lot like they're opening late. It won't stop the spark, but it will make it so that every so often the fuel doesn't show up until after the (spark plug) arc quenches. Thus, a misfire is detected because all of that unburnt fuel shows up at the upstream oxygen sensor.