2011 Ram 1500 5.7 Liter Misfire
Here is a case study that I have just completed. This Ram 1500 has a misfire that has had a lot of parts installed trying to fix it, I hope this helps.
Wow, you are the mastermind of in cylinder pressure diagnostics ! Could carbon be causing the rings to stick in their grooves and not seal?
Steve That could be a possible cause, but usually the oil ring is the ring that will get stuck with carbon or sludge. This engine was over heated and damaged the piston and cylinder bore.
So Kool Mr. Thompson, thanks for all you do. I have gained more knowledge from watching your case studies, it makes all the years of trial and errors fit like a puzzle. Thanks again.
I am always learning something new from you Bernie. Thank you for taking the time to share with us!
Thank you Bernie. I learn something every time you post and i look forward to the next case study you publish. We're building a new diagnostic cart and training the team to think like you. We'll be equipping the cart with your tools.
Thanks Bernie! The information you share with us is greatly appreciated and invaluable to us average Joe's.
Justin The fuel trim was -7% on bank 2 and -17% on bank 1, this is a difference of about 10 %. The fuel was in control switching states from rich to lean , and from lean to rich on both banks. The misfire was not a dead miss as seen by the mode 6 data. If the cylinder was rich enough to wash the rings out there would be a greater fuel trim difference between the two banks. However a great test…
Great! IMHO. The asymmetry in the pressure waveform along with the lack of valve train problems also points to a ring/piston/cylinder sealing issue, just like the crankcase pressure waveform indicated.
In the video it appears and is mentioned that the PCM shut off the injector. I wonder what effect that would have on a fuel wash issue.
Olle The ECM did not stop the control of the injector, the ignition coil was shut off due to the resistor that I placed in the circuit to replace the ignition coil. During the normal operation of the engine it did not stop the control of the injector or ignition coil.