Experts,

Here's the situation.....
I have a 2001 Dodge Ram 1500 5.2 197K as a project truck for me and my boys + a little girl that actually has more interest than them.

The truck is now misfiring (P0301) it never misfired prior to the work we've done to it.

Here is what has been done so that yall have the details needed to hopefully help us out.

New Spark Plugs. (6721 Bosch Premium)
New Wires (Duracrap)
New Coil Pack (1A Auto)
Removed throttle body for cleaning

Aside from replacing the u joints and installing a leveling kit that is all that we've done thus far.

Below is what we've done to try to remedy the situation.

Reinstall original wire to cylinder 1 (no change)
Remove and replace sparkplug for cylinder 1 (no change)
Reroute wiring to ensure no arcing (verified at night as well)
Verify wires are good by means of continuity

None of this has helped

Symptoms leading to misfire seem to be at a prolonged idle or cold morning starts. While engine is warm and driving it "seems" not to have any issues.

We did have a very loud tick in one cylinder (driver side) after spark plug change that mysteriously went away about 5 mintues of running and hasn't come back.

Any thoughts one what our next logical step should be?

I'm sure we did something to aggrevate this....but for an old beater that were having fun working on at night, I guess it's been worth it.

 

Might want to check the cap and rotor. If those haven't been replaced, now would be a good time. Also, these motors don't tend to work well with Bosch spark plugs. These motors tend to run best using copper plugs. As part of the throttle body cleaning, be sure to check and clean the idle air controller on the back of the throttle body.

Lastly, with the high mileage you have on that motor, be sure to check the intake plenum gasket for leaking oil. More information on that can be found here - https://dodgeforum.com/forum/2nd-gen...um-thread.html

 

Yep, get rid of the platinum plugs, install some good ol' coppers. Likely fix your issue. (wouldn't hurt to reset the PCM as well.)

 

Thanks Gents! I'll pick up some new plugs and update you with a status. Hopefully it fixes the issue.

 

Gents as of today, the autolite copper plugs "seems" to have fixed the issue as I haven't thrown a misfire code sine I replaced them. I'll keep you updated if anything changes. Thanks all!

 

From what I can understand, it's easier to make a spark on the copper plugs than the platinum or iridium. The copper plugs don't last as long, but I like to change plugs sooner anyway, that way they come out easier. Our trucks have one coil for 8 plugs, so there isn't a lot of time to build a really strong spark. Most newer vehicles have 1 coil for two cylinders or a coil for each cylinder. They have more time for coil saturation to make a better spark for the iridium/ platinum plugs. NGK has new Ruthenium plugs that are supposed to spark easy and last longer, but they are really expensive.

 

Just an FYI, I'm running Autolite double platinum plugs with the factory gap setting in my 5.9 motor and have not had a bit of trouble with them. I have experienced issues with Bosch platinum spark plugs, as the Bosch plugs don't have a pronounced tip like the Autolite plugs do. I used to run the same style Autolite plug in my '82 Dodge Ram 150 with a 225 /6 motor and experienced no issues.

 

It seems to be really random which trucks will tolerate them, and which won't. But, for mystery misfires, the rare-earth plugs are the first thing I recommend changing.

 

I agree completely. If I experienced any issue with the Autolite double platinum plugs I'm running, I'd yank them out quick. I've found that Bosch platinum plugs certainly don't work in all vehicles, however, Autolite platinum plugs seem to work better in many applications. As such, I typically use Bosch plugs on German vehicles where they came as OEM spark plugs.

I've got to admit that Autolite makes a pretty decent spark plug for a wide range of applications.