The truck is a 2005 Dodge Ram 1500, 5.7 Hemi, about 89,000 Kilometres. I have a P0300 code with nothing else, it seems to only happen on restarts and never from a cold start that I am aware of and until recently it was very intermittent and would not happen for months now it seem to happening a lot more often. I have changed spark plugs, wires from a Dodge dealer so Champion plugs and factory wires, I also changed the EGR valve. I am not sure where I should go from here I have bluetooth OBD 2 reader with the Torque app but not sure what I should be looking for. Any help as where I should check next would be helpful, I am cleaning out my Throttle body tomorrow and if there is something else I should check while I am there let me know. Thanks for any help you can give me.

 

Nothing? No ideas? Asked wrong? Not enough details? Anything?

 

Are you feeling a misfire?

 

No misfire that I can feel. It happens only at low RPM's I can throttle through the issue if I rev the engine as it about to stall, it runs fine after I get through the rough idle. It is starting to happen even on cold starts now. I am just at a loss, nothing I read or researched seems to give me any answer. I am game to try anything at this point. So any suggestions are welcome. It runs like a dream when it is not about to stall, it idles just round 520 RPM but now it just feels like it wants to stall out for no reason and the only code I get it P0300.

 

Only a thought. Maybe check for the common issue of a broken valve spring. Although it doesnt completely make sense to do this....as you mention at times it runs like a dream and with a broken valve spring theoretically it should run rough all the time. But its a guess...possibly a broken valve spring is sufficient to close the valve for proper compression and others times it is not. ???

 

Thanks I will look into the valve springs, I might as well since I am just at a loss. I am going to also go over my electrical system to make sure nothing in the area is the issue. Any other ideas I am open to looking into if anyone else has suggestions.

 

It is not the valve springs, so I guess I am SOL for ideas at this point in time. Still going to give the electrical a once over from top to bottom and hopefully it I find something there, going crazy trying to figure this one out.

 

Just a total guess here for me now. You might consider crankshaft and/or camshaft sensor ? Seems your problem is more pronounced when cold. Maybe do a resistance check on the sensors when cold ? Or simply put a new one on one at a time? I would start with crank sensor.

 

did you figure out the problem ?

 

I have finally figured it out so sorry for not replying it was the O2 sensors, I replaced all 4 as I got a real good deal on some genuine Dodge parts so I went with all of them being replaced. It was not coming up in my codes anywhere as I was getting was a P0300. Everyone I had spoken to told me there was no way that was the issue but I should have went with my gut feeling. I talked to 3 different Dodge mechanics, two people I know who are mechanics as well and they all said it made no sense at all and I should be looking elsewhere. I changed all 4 few weeks ago and all my issues went away. I only figured it out when I went for my e-test and I failed because two things were not reading in the test one was the catalytic convertor and the other was the O2 sensors. The parts cost me $80.00 for all 4. So a $20 issue was haunting me for a long time. It passed the second e-test with no issues at all so unless something happens I assume it is fixed.