Lots of reading to do;
http://dodgeram.org/tech/gas/Trouble/ping.htm

Tons of good information. The suggestion of using a black light dye in the motor oil and checking the bottom of the intake after driving a few hundred miles is definitely an interesting method and worth trying if you feel like experimentation.

Also check out this video:


He's got some other good repair videos as well. Definitely worth checking them out with you being new to the truck.

 

I was just doing some searching on line, looking for information on magnum engines. I came across an article on the magnum 3.9 v6 engine that described the same exact problem your having with the pining noise. The article stated that the noise is coming from the timing chain, and the fix is to replace the timing chain and add a tensioner to the new timing chain, and this will fix the problem. So I guess this is a common problem on the magnum v6 engines. You can find the information in the link below.


http://www.google.com/url?sa=t&rct=j...70810081,d.aWw

 

Yikes, well I definitely don't want to try that then. There's a reason certain things on the internet only appear in one place!

Thank you guys for the links I'm going to check this stuff out and hopefully get to the bottom of the bad idle and other noises. I'm going to fix the hole in the exhaust first so that stops driving me crazy.

EDIT: Wow that guy's channel is great! He has a 98 as well.

 

Id be willing to bet your plenums no good. Its a huge known problem with magnum motors, and those vacuum tests are not good indicators it wont tell you anything unless you have a huge vac leak goin on. Timing chains are also known to stretch in magnums and replacing them with a good double roller is also recommended.

 

Changed cap and rotor over the weekend (never did that before on any car!), other than swapping cyl 3 and 4 on reconnect everything went well and my idle is smoother now and the ping got a little quieter! Like was shown in the video, my cap was really worn on all the points, and the center coil input point had no spring at all!

New upstream O2 sensor this weekend as well.

One of the TSBs linked in that PDF showed re-routing of the IGN coil wire away from the plug wires making things run better, I'm probably going to try that next for good measure.

The plug wires aren't factory but they looked sort of new so I left them alone for now, but I am thinking replacement might be a good idea if they don't cost too much.

I have factory PCV valve on order from the dealer ($6 but rumor has it the Mopar one isn't noisy and works better).

 

Sounds like you're off to a great start!

 

Noticed a new one today, it's probably been happening for a while but...

On a cold start where it sat all night, thing runs pretty rough and pings like mad for the first 30 seconds (enough to set off the CEL sometimes), but after that it smooths out and is normal after about 2 minutes.

I don't get any other misfire codes after the engine warms up.

 

When is the last time it was tuned up?

 

So far since I bought it:

- Plugs
- Cap/rotor
- PCV valve

And today I did the TSB to reroute the IGN coil wire away from the spark plug wires, and on the first cold start after I didn't hear the pinging. Only time will tell if this continues to work!

Also I bought a new IGN coil since the current one is a little rusty and the little plates are separating at the end.

 

Good plan on coil.