P303 code????

[MisterB]

So I have an issue with #3 cylinder misfire. I changed the plugs, I changed the ignition coil on 3. I changed the injector on 3 and fuel pressure regulator sensor today and now the truck is running worse. Any help would be much appreciated to figure this mess out. I don't have any tech gadgets or know-how too use them. I am frustrated too beat hell right now......

 

[RamRod37]

if you changed all that and still missing its can only be two things at this point broken wire going to coil or injector or the well-known hemi issue seized lifter and eat cam lobe

 

[MisterB]

I am wondering if the injector is causing the issue, into believing I should replace all the injectors to be the same, because what I noticed with the new injector, is the sprayer holes are larger in diameter then the the one I took out. Could this cause the issue as in its injecting more fuel then the others, throwing the computer off?? This is a whole new learning curve for me trying too diagnose this type of problems. I have a sense of what's kind of going on, but kind of scratching my head at the same time.

 

[RamRod37]

I do not think so need to do a compression check on cylinder 3

 

[RamRod37]

below is what mine done to Cylinder 6 it's a well known issue with the hemi mine had three other lobes that was going as well

Could be a valve spring or valve issue but given track record with lifter/cam issues my bet is on the lifter

 

[Burla]

So I have an issue with #3 cylinder misfire. I changed the plugs, I changed the ignition coil on 3. I changed the injector on 3 and fuel pressure regulator sensor today and now the truck is running worse. Any help would be much appreciated to figure this mess out. I don't have any tech gadgets or know-how too use them. I am frustrated too beat hell right now......

Is this on a 4 gen 2015 ram? Here is dyi cam install. There is little hope it is something other then cam when you get p0303 especially before they beefed up the needle bearings in 2016 I believe. Sorry man, this is the main weakness on these 4 gen rams.

You see the bottom pics in the post above, that is what it looks like when a needle bearing fails. The other photo's of cam wear is what happens when needle bearings are in tact, but still wear down cam. Either way it is fatal, but needle bearing fails 2009-2015 rams just make it more likely it is the cam and that metal is in engine. Check oil control valve for metal, determine of you can replace cam or need a new engine.

 

[MisterB]

I only have 90k miles on the truck and your saying change the cam, already? If that's the case then the truck will sit until I figure out what too do with it. Thanks

 

[RamRod37]

yeah 90k mile that sucks but happens do a compression check or pull valve cover check for lose rockers on cylinder 3

 

[Burla]

I only have 90k miles on the truck and your saying change the cam, already? If that's the case then the truck will sit until I figure out what too do with it. Thanks

The average cam fail for 4 gen rams pre larger needle bearings 2009-2015 is between 70k miles and 130k miles from the other ram forum. Mind you this is apprx, you can get cam fails even under 70k miles and over 130k miles, but this was the largest group when they started tracking it. If you fix it, look into lubrication strategies and hemi tick lubrication, maybe prevent it in the first place. Sorry for your troubles, a lot of us are in the same boat.

You can still try some other things to make sure, but this is for sure the most likely culprit sad to say. Check that oil control valve, if it isnt full of metal that is good news, it can be fixed with less risk of metal tanking a new cam/lifter job.

 

[MisterB]

Further analysis, after i do a reset and no check engine light. I have noticed the truck runs okay after it's at full temp, but when cruising around 60mph and I kick it down. It's then I get the check engine light and the truck start running rough with a stuttering and chugging like effect. Could this be a sensor. After the truck cools down and I drive it again it drives normal, until I get on the throttle.

 

[Burla]

If it was a sensor you would get a code for that. Sensors usually shut down an engine or send it into limp mode as opposed to make it run bad, but could possibly mess up fuel/air/spark ratio and in theory could make it run rough. Just not likley, and run the codes everytime if you are curious.

If you contimue to get general misfore code and p0303 it has a 95% chance the cam lob on that lifter is toast. Eventually, the truck wont run, I'd fix it.

 

[Dodge 1500 4X4]

Pull the Valve cover off on drivers' side and check for rocker arm movement, Bank one is
1,3,5,7, let us know