2008 3.7 cylinder 3 misfire

[nathantc]

new plugs
new coils
just replaced all the injectors with the 12 hole Denso 12582704 injectors

has not thrown a code since i reset the PCM after the injector swap. idles much better. much more responsive, holds and picks up speed in OD at hwy speeds much better. that said i know it has a lot to do with 180k miles on the old ones vs the new ones.

after all that its not throwing a code, the injectors where installed this morning.
can't find a leak on the intak around cylinder 3.
still feel a slight stumble at idle, never was a detectable miss at any rpm off idle.

my question is this. could it still be a lash adjuster even though there is absolutely no noise from the engine. i dont have a compression tester just yet, might be picking up one soon though. the miss is barely noticable. almost non existent. but if i let the truck idle long enough it will throw a code.

researching now if solid lash adjustors would be an upgrade over the hydraulic.

 

[Fast69Mopar]

new plugs
new coils
just replaced all the injectors with the 12 hole Denso 12582704 injectors

has not thrown a code since i reset the PCM after the injector swap. idles much better. much more responsive, holds and picks up speed in OD at hwy speeds much better. that said i know it has a lot to do with 180k miles on the old ones vs the new ones.

after all that its not throwing a code, the injectors where installed this morning.
can't find a leak on the intak around cylinder 3.
still feel a slight stumble at idle, never was a detectable miss at any rpm off idle.

my question is this. could it still be a lash adjuster even though there is absolutely no noise from the engine. i dont have a compression tester just yet, might be picking up one soon though. the miss is barely noticable. almost non existent. but if i let the truck idle long enough it will throw a code.

researching now if solid lash adjustors would be an upgrade over the hydraulic.

Without knowing the results from a compression test or the other really important test, the cylinder leakdown test, my money is on the intake and exhaust valves not dealing properly to their respective valve seats. A leakdown test will tell the tale.

 

[nathantc]

Without knowing the results from a compression test or the other really important test, the cylinder leakdown test, my money is on the intake and exhaust valves not dealing properly to their respective valve seats. A leakdown test will tell the tale.

i need to go get a compression tester. other than the barely noticeable idle the truck runs amazing. much more power than it had before the plugs, coils, and especially injectors. i can't help but think a compression issue would be felt across the rpm range.

 

[Fast69Mopar]

i need to go get a compression tester. other than the barely noticeable idle the truck runs amazing. much more power than it had before the plugs, coils, and especially injectors. i can't help but think a compression issue would be felt across the rpm range.

Not necessarily in the compression issue. It can be a funny bird. Low speed operation is what is affected the most by a cylinder not building enough cylinder pressure.

Make sure you get the leakdown tester too.