Unfortunate report on new Ram

carringb wrote:

Turtle n Peeps wrote:

Bovine excrement. Bent valves don't seal. Bent valves get bent because there was interference with something...….like a piston. If the guide is a little tight the valve will stick open. When this happens the piston will come up and whack it. When this happens the valve bends. When this happens the valve does not seal and you get a misfire code.

Next time you're back at the dealer get real close to the service writers face; talk real slow and real quiet and ask: "how does a bent valve seal and not show up in a compression test or leak down test?"

^I'm in agreement with this as well. A single valve being damaged pre-assembly, sure. If the vendor's and FCA's QA's processes were completely inoperative at the time of your build. 2 vales? Not a chance.

BTW - The dealer absolutely should have done a compression test before even taking the first plug out. A "relative compression" would have shown them the weak cylinder just by cranking it over with the computer hooked up. At that point, this would be cause to dig deeper (and it would also rule out bad cause as a primary cause, unless it was running so lean it burned up a valve, but there would be other codes for that as well). Once the relative compression test shown a fail result, the diagnostics guide would call for those more invasive tests.

Again 100% correct and on the money! This is exactly what should have been done. You can work on my cars anytime you want Bryan!

BTW as far as the piston damage. The old hemi's valves will hit the piston almost flat so they won't nick the piston like a BBC would. I don't know if the new hemi's are the same? Never had one apart so I don't know the valve angles?

OP I'm glad your getting a new head. This should fix you right up and running correctly again.