[Red91RTtoo]

Hi-ya folks. I used to be on the forum as Red91RT but the password reset has not sent me my email all day. I gave up and registered a new account. Back then I had a 2013 200 first that I bought a HemiFever Tuning e85 tune and dropped .6 to .7 on my ET’s at Rocky Mountain Raceway. Made the semi-notorious sewer pipe intake. Then I traded for a 2016 FWD 200 3.6 in summer of 2017. I raced a bit with it but got too busy to tune it and report any more. Then sold that to buy my wife a car.

well… I’ve been daily driving my toys for too many miles, even though I work from home last few years. So I’m interested in a 2015 3.6 AWD this time. Only problem is misfires that lady hasn’t found a shop to fix. She’s done plugs and “wires” (I assume shops did coils). First shop gave up and referred her to one that read misfire on 3 and 4. It has 150,000 miles.

I want to buy and repair and use as my daily (and play and tune it a little).

I have researched and found the most likely remaining thing, especially if it really had a tune up (she said coolant too) is the left cylinder head issue. But a 2015 surprises me it would have that like the ‘11’s and ‘12’s. Also, with it being misfire on 3 and 4 that’s both banks and I find it hard to believe it’s both heads.

my guess otherwise is a vacuum leak. But looking for any thoughts on what else is likely and has been found to fix (other than heads) before I make an offer Friday.

 

[200_S_AWD]

Welcome home! 😉 As long as it is not a 'mechanical' issue causing the misfire (P0303 & P0304?), it should be fairly easy to fix. Always diagnose first.

Is there any ticking at idle? If a roller rocker lost its needles, that could be fixed without pulling the head.
Is it a warm misfire or all the time?
A compression test may not show this and it may need a cylinder leak-down test to determine a valve problem.

The Pentastar head problem affected some early ones, it can still happen but is rare.
A vacuum leak would tend to cause a fast idle, but a prolonged lean-mixture condition could burn valves.

 

[Red91RTtoo]

Oh, awesome help! Been working on cars for 35 years and didn’t even think of that—and I’d had some of the lash adjusters fail in my T3 engine years and years ago.

Very cool. I’ve a couple other things to listen for and check when I go look. Thank you!