2014 Ram R/T, P0300 & P0306 Misfire Detected Help

[aramos3]

I have been getting the P0300, & P0306 CEL trouble codes, I have reset them twice and they come back after a few days every time. What is the process of diagnosing the issue. The truck feels normal cant say it sounds different or a noticeable drop in power. The truck has the factory Iridium 100k plugs, would running LT's and a tune for the last 40k miles cause a quicker deterioration of the plugs hence requiring early replacement intervals?

Specs: 2014 Ram R/T 67,000 miles 5.7 8 speed
Mods: ARH Catted LT's, Hemifever 91 Tune

 

[RysRam]

Pull the driver's side valve cover, pull the fuel pump fuse and turn the key. Watch to see if all of the rocker arms are moving.

 

[aramos3]

Pull the driver's side valve cover, pull the fuel pump fuse and turn the key. Watch to see if all of the rocker arms are moving.

Cylinder 6 is in the passenger side, shouldn't I be looking into the passenger side.

 

[RysRam]

Cylinder 6 is in the passenger side, shouldn't I be looking into the passenger side.

My bad, pull ps valve cover. At this point it might make most sense to rule out the worst possible scenario before you start swapping coil packs around. I hope it's something simple.

 

[huntergreen]

If it were me, my first step would be to pull a spark plugs and take a look at it. If ok I would move the coil pack and see if misfire follows the coil. If all that checks ok, I would use my 5 year 100000 mile warranty.

 

[aramos3]

If it were me, my first step would be to pull a spark plugs and take a look at it. If ok I would move the coil pack and see if misfire follows the coil. If all that checks ok, I would use my 5 year 100000 mile warranty.

Swapping coils might be the easiest approach, If the misfire follows the coil that would indicate a faulty coil, simple fix. I am hoping it's that simple. I would honestly like to avoid the dealer since I have aftermarket parts that I can see them denying a claim.

 

[huntergreen]

Swapping coils might be the easiest approach, If the misfire follows the coil that would indicate a faulty coil, simple fix. I am hoping it's that simple. I would honestly like to avoid the dealer since I have aftermarket parts that I can see them denying a claim.

.

Understood, but it's possible you are in the beginning stage of the dreaded lifter and cam failure. I would return to stock if it's not a coil or plug issue.

 

[big13]

I had same problem and same codes. I cleared them and they came back, I thought it was a coil maybe going bad or a spark plug problem.... Here IS THE KICKER. I took it to the dealership. IT IS actually a SOFTWARE upgrade that you need. It was covered under warrenty, a recall.

 

[big13]

this is my thread from June 19th

http://www.ramforum.com/threads/engine-trouble-misfire-p0300.121907/#post-1757602

 

[Alan Summers]

Hey big13, was the software upgrade covered under warranty? Upgrades should be for the life of the vehicle IMO! Did they do it while you waited? I wonder if 2010's have software upgrades pending or in a TB somewhere...

 

[aramos3]

I had same problem and same codes. I cleared them and they came back, I thought it was a coil maybe going bad or a spark plug problem.... Here IS THE KICKER. I took it to the dealership. IT IS actually a SOFTWARE upgrade that you need. It was covered under warrenty, a recall.

What year is your truck and how many miles did you have at the time of the engine code.

 

[big13]

Hey big13, was the software upgrade covered under warranty? Upgrades should be for the life of the vehicle IMO! Did they do it while you waited? I wonder if 2010's have software upgrades pending or in a TB somewhere...

Yes covered under warranty, my truck is 2013 with 80,000km or 50,000 miles

 

[aramos3]

Check engine light came back on, and it's in the same cylinder ruling out a bad coil.

 

[aramos3]

Just got back from the dealer, they claim the iridium spark plugs are arching and the coil is bad, they want $550 to replace the coil and 2 spark plugs, which is absurd.

 

[RysRam]

Well, they're right, spark plugs do in fact arc.

Did they advise of why they think it's the plugs and coil? Or are they using the spray and pray repair protocol lol....

 

[aramos3]

Well, they're right, spark plugs do in fact arc.

Did they advise of why they think it's the plugs and coil? Or are they using the spray and pray repair protocol lol....

I'm not sure how they concluded that the coil and plugs where bad. I swapped coil and assumed the plugs where good since they are good for 100k . But they claim a bad coil and plugs. As what is absurd is the pricing $80 worth or parts and 1/2 hr worth of work and they want $550

 

[Lee Peterson]

Id swap the 2 plugs in cylinder 6 with another cylinder before dropping that much coin.

 

[Tach_tech]

I'm not sure how they concluded that the coil and plugs where bad. I swapped coil and assumed the plugs where good since they are good for 100k . But they claim a bad coil and plugs. As what is absurd is the pricing $80 worth or parts and 1/2 hr worth of work and they want $550

It’s more than $80 worth of parts and 1/2hr labour for a tune up and a coil on a hemi. Remember you have 16 plugs. Labour time for a hemi tune up ranges from 2-3hrs depending on the shop. We charge 2.2hr. Personally I can do one in just under 45mins, but I’ve also been doing this for 10 years, done them a hundred times and know the tricks.

If you have the time and tools just do it yourself, but guarantee you’re not getting it done in 30 mins.

For future reference to diagnose a misfire. Start with swapping plugs from cylinder to cylinder regardless how they look, as well swap the coil. Clear codes and wait for misfire to return. If it’s still on the same cylinder, swap an injector. If that’s still not it and you’ve checked power/grounds for the coil/injector next is compression test and a leak down test. Then start tearing the engine apart.

 

[aramos3]

It’s more than $80 worth of parts and 1/2hr labour for a tune up and a coil on a hemi. Remember you have 16 plugs. Labour time for a hemi tune up ranges from 2-3hrs depending on the shop. We charge 2.2hr. Personally I can do one in just under 45mins, but I’ve also been doing this for 10 years, done them a hundred times and know the tricks.

If you have the time and tools just do it yourself, but guarantee you’re not getting it done in 30 mins.

For future reference to diagnose a misfire. Start with swapping plugs from cylinder to cylinder regardless how they look, as well swap the coil. Clear codes and wait for misfire to return. If it’s still on the same cylinder, swap an injector. If that’s still not it and you’ve checked power/grounds for the coil/injector next is compression test and a leak down test. Then start tearing the engine apart.

They quoted me $550 for one coil and 2 spark plugs not a tune up or additional services . Two irridium spark plugs can be had for $20 and a single coil $40. I can replace the coil and the two spark plugs at cyclinder 6 in less than 15 minutes. And I initially did trouble shoot I swapped plugs and coil with cyclinder 8 and the same CEL came up in cyclinder 6. P0306

 

[Tach_tech]

They quoted me $550 for one coil and 2 spark plugs not a tune up or additional services . Two irridium spark plugs can be had for $20 and a single coil $40. I can replace the coil and the two spark plugs at cyclinder 6 in less than 15 minutes. And I initially did trouble shoot I swapped plugs and coil with cyclinder 8 and the same CEL came up in cyclinder 6. P0306

At the price they quoted you I assumed it was for a full tune up. You said before you only swapped the coil and assumed the plugs were good since the interval is 100k.

Wouldn’t hurt to take the coil and plugs out of cylinder 6 and inspect for any signs of carbon tracking. Then swap with a cylinder again, disconnect the battery for 30 mins, and see what code comes back.