2015 5.7 8 speed Hard to start very rough idle...please help if you can

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Elevated 2013

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Hay Guys, you may have a collapse hydraulic lifter, there's no valve lash adjustment on the rocker arm assembly but you will be able to see a dead rocker did you replace the push rods
how's your oil pressure you said you replaced the pump, did you do a compression test these are a few ideas from the old days, thats on of the reasons I came back to Ram, sick and tired of the cam phasers duel timing chains and tensioners had my share of problems

If he has the valve covers off and can either get the engine to run enough or turns the crank by hand, he could watch the rocker arms go up and down as well as the valves. If it’s a lifter there should be a big difference in the distance it goes up and down compared to the good cylinders.
 
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Shortbus 50

Shortbus 50

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Yes, COP are good. Push rods where in great shape. it now has hellcat oil pump and lifters. oil pressure was normal. All test where done 700 miles after cam swap. Leak down, compression, vacuum etc. all was great. She ran so good for almost 2 months.
 
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Shortbus 50

Shortbus 50

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Yes that test is what confirmed the bad lifter destroyed cam back in july. That repair cost me almost $6000 with me doing all of the labor. But I also replaced with upgraded all new ignition and fuel injectors. Did't change lbs on injectors, just got a good brand.
 

Sly Dvl

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You have to check fuel pressure. All of your symptoms mimic bad fuel pressure or a failing pump. Smelling a rich exhaust or seeing black or wet plugs is in no way an indication of acceptable fuel pressure. Liquid fuel won't burn, and if the pressure is low atomization doesn't occur and it will smell rich.
 
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Shortbus 50

Shortbus 50

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No shrader valve, where do I put adapter?

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Elevated 2013

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No shrader valve, where do I put adapter?

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You can’t as that was said in an earlier post but it would’ve been a good test to do. I wonder if the DiabloSport tuner could tell you?? I don’t know as I don’t remember.
 
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Shortbus 50

Shortbus 50

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Oh ****. That's right, I have an obd2 Bluetooth that does. But yeah, I believe the Diablo does but not as detailed. I will check it asap, but got a lead today with a continuity check. Found a bad ground somewhere in the engine harness. I believe it's at my O2 sensor.

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Elevated 2013

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And that would make sense for it being too rich if that sensor is reading too lean or if there’s an exhaust leak that is somehow letting air in just before it.
 
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Shortbus 50

Shortbus 50

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Update...found a short in a line to the pcm. Tested continuity on negative terminal and got a hit on a hot pin on the pcm connector. Also showing a short at one of the o2 sensors on bank 2. Update you guys when I get more into it
 

rltaylor46

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I read how much y'all are trying to help Miguel smith with his problem. Now I'm reading Shortbus 50's post. And again, all of you are givin' him your best ideas and help.

Congrat's y'all, and a big "Thank You" for being helpful and cool.
 

Elevated 2013

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I love helping others! Plus, others have helped me. So like them, I’m just paying it forward and Praying for good kharma to finally find me 44 years later!! Lol.
 
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