Random misfire code with popping from the exhaust

Hey guys,

My 2004, 5.7 is running rough and has a random misfire code. Initially I changed plugs and EGR valve as it was time for those, thinking that was it. It didn't fix the rough running and now the engine is making a popping sound from the exhaust when driving and not accelerating. It goes away on acceleration. Any ideas what that might be and how to diagnose it?

Thanks!

My son's 5.7 had the same thing, found a bent pushrod. Replaced it and the misfire code, the rough idle and the motor noise all went away. Pull the valve covers and have a look.

My 2016 Challenger Scat Pack did this a few weeks ago out of the blue - check engine light came on after a little while. I took it to a shop that scanned it & the code was showing "multiple misfire" - then he cleared the code & it has not done this again since.

I had a couple 4.6 fords that did that sort of thing and threw misfire codes. The coil on plugs had a boot that was rotted away on a few. I replaced them all on both cars when it happened and solved it all. Just a thought.

My run in with random misfire codes was broken valve springs. It costs nothing to pull the valve cover off and check the valve train while rotating the engine. If you have a way to test compression- thats even better. Start there. If your tests/inspection yield nothing, you may have to go into the engine. I personally have not seen an injector or coil pack throw a multiple misfire code, but I do not work on strictly chrysler products every single day.

As stated, check for broken valve springs.

The earlier Gen 3 Hemi's are kind of noted for broken valve springs when you start getting some miles on them.
It's supposedly from spring oscillation.
They started putting a stamped metal collar around the spring that went halfway up the spring in about 2006 to stop the spring oscillation to stop them from breaking.

as i know nothing about the gen3 hemis, are the valve springs used on them beehive springs ?
TIA for educating this old dawg to new trix.........

Yes they are beehive style springs.
I personally know of several people who have had the earlier valve springs break (besides myself).

There is a YouTube channel i watch sometimes- I Do Cars- the gentleman owns a automotive resale business- he buys core engines and tears them apart to see why they failed and goes from there. He made mention of something that made sense and made me cringe at the same time-" Thanks Chrysler for making valve springs a maintenance item". Haha

A cranking compression test will not always show a broken or weak valve spring as it may have enough to contain "static" compression but not running with the pressure of combustion

Thanks for the tips guys!

I'll post an update when I get it figured out.

Agree 100%! A running compression test is the best way to pick out weak or broken valve springs. BTDT. Got my butt kicked around with a wandering misfire on a Vette many, many years ago. I now do running compression tests right after cranking compression tests. Learned the hard way.

Once again guys, thanks for clarification, I for one don't forget the conversation we all had a while ago about this, thats why I just generically coined compression test. No arguments here. And, waiting for update!

I had check engine light come on my 2010 hemi truck for misfire cylinder number 5. I replaced the coil pack and the code went away and has been running fine since then, and that was about five years ago.