Cylinder 2 Misfire P0302 - 2019 Ram 1500

[trobin0406]

I'm having some trouble with my 2019 Ram 1500 5.7 Hemi Limited eTorque. I've been getting a cylinder 2 misfire at idle, but it's intermittent. It's not a hard miss, just a faint one that happens sometimes.

I've already tried replacing the injector with a new one from Mopar and swapped the ignition coil with cylinder 4, but that didn't resolve the issue. I also have new spark plugs that I haven't installed yet, but the old ones were replaced around 115k miles.

I've been using a scan tool and have noticed that it counts about 12-18 misfires in 30 seconds while sitting at a light. I change my oil every 7500 miles and have over 170k on the truck. The truck runs great otherwise which makes me feel like its not a wiped cam.

Has anyone else experienced this issue? Any suggestions or recommendations would be greatly appreciated.

 

[SD Rebel]

At this point, you covered the basics, I would take it to a trusted independent shop familiar with the Hemi 5.7L and have them diagnose it.

 

[OCD Solutions]

I've been chasing that gremlin for the last 2 years only mine is Cyl 8.
I'm sure it indicates an issue but it can't be too serious since it runs smooth as silk for patches as well. It just seems to be very sensitive to who's fuel I buy and what grade I get. I've swapped from reg to mid grade with a tank of premium thrown in from time to time.

My issues started when we moved and I started buying fuel at a different place. I quickly discovered that as long as I buy decent fuel, I was fine, but, it takes a tank or two of Premium to clear out the offending fuel. Kroger and Chevron are my current fuel of choice. Race Trac was the place up the road that started this all off.

It's actually been running good for several months until I recently filled up at a Dollar General in some po-dunk little backwoods town and got a slug of water that took several tanks to work out.

 

[trobin0406]

@OCD Solutions - That seems to make sense. I stopped at a Shell on my way to Orlando and I struggled the whole trip with misfires and that's what initially made me think it was the injector. I ran a bottle of injector cleaner on the next fill up and it helped substantially until it ran through and started to act up again.

Lately though i have been get gas at reputable places but i haven't tried making the switch to premium or mid grade. Maybe I will give that a shot for a few weeks and see how it helps.

 

[Cbty2050]

Have you pulled the plugs and inspected them? Have you checked the compression? Even a simple clear flood you may be able to notice a low compression in a cylinder.

 

[trobin0406]

I was thinking of doing that this coming up weekend and just swap the plugs since i already purchased. I can try the clear flood mode when i head to lunch to see if i hear anything. I just think a low compression would exhibit a misfire all of the time and throughout the RPM range.

 

[Cbty2050]

I just think a low compression would exhibit a misfire all of the time and throughout the RPM range.

An example of a low compression only missing at idle. The 3.6 Pentastar would get a misfire at idle, not on accel or cruising. Intake valves wouldn't seal. You would have about 110psi or less on a cylinder, all others would be around 185psi. Slightly low compression acts differently than no/very low compression. Surprisingly you can hear the low compression on the 3.6 doing a clear flood, then verify w/ a relative or actual compression test.

 

[trobin0406]

Just did a clear flood and there was no difference in the engine cadence.

I will try to get a compression test done in the next few days and report back. Maybe i will do the whole bank to have numbers to compare to.

 

[Richard320]

Spark plugs would have been the first thing I'd go after. And while I had the coil off anyway, that's when it gets swapped with another. All it takes is a pinhole in the spark plug boot, cracked porcelain, or some carbon tracking and you have a misfire.