2012 Ram 1500 5.7L P0300 code and engine noise after cam/lifter swap

[Chan24]

Hey everyone, I am looking for any help I can get on my cam/lifter replacement job on a 2012 Ram 1500 5.7L.

One of the lifters ate a cam lobe and caused a cylinder 5 misfire. I decided to replace the camshaft and lifters because I didn't find any metal shavings on any of the MDS solenoids or in the oil. Because of that, I decided to replace the cam (Mopar) and lifters (Mopar). I also replaced MDS solenoids, VVT actuator, timing chain, both sprockets, damper, tensioner, Melling HV oil pump, and push rods. Before I started the truck, I turned it over by hand to make sure everything was seated correctly. When I started it, I heard a loud metallic knock from the driver's side that went away immediately. After the truck idled for about a minute, it started running rough and was shuddering. This happened at about 800 rpms and it threw a P0300 code.

I took apart the engine to check timing, lifter/cam damage, and or unseated push rods. I was unable to find any obvious issues or incorrect installation. I bought a better scanner and found that cylinders 4 and 6 are showing misfires. I checked spark plugs and ignition coils by swapping them to other cylinders that were operating correctly. I also tested the fuel injectors to verify they could fire, and there weren't any blockages. The misfires remained on cylinders 4 and 6. I checked compression on all cylinders and got a range from 200-225psi. Cylinders 4 and 6 were 215 and 225 psi. I also did a smoke test on the intake, but was unable to find any leaks.

I think I covered everything I have replaced and or done when trying to diagnose this issue. Thank you in advance for any help that you guys can give me!

 

[stevenmicheal]

From what you described, it sounds like you've already ruled out a lot of the common stuff. If timing and compression are good, I'd start looking closely at the wiring to the injectors and coils on 4 and 6, plus double check the cam and crank signals with a scan tool. At this point, I'd honestly take it to a RAM dealership and have them run a full diagnostic, because sometimes they can spot something that's easy to miss after a big repair like this. I know how frustrating these Hemi lifter jobs can be.

 

[EdGs]

You said Mopar parts. Were they from a reputable source? Lots of counterfeit parts out there, in counterfeit packaging, too.

I doubt this is possible, but any chance the injector or coil wires for 4 and 6 got reversed?

Sorry I'm not much help. Hope you find the issue and it's a simple fix.

 

[henriviera]

Hi Chan, I’m going trough the same stuff and maybe you can help resolving this mistery. My mechanic got done the job today and replaced lifters, timing components, he said cam shaft was good. Replaced oil pump just because of all the hard parts that he found in engine oil pan. So now there is a light on for misfire. He will try swapping the coils and see if that would do. Please let me know if you get to the bottom of that. Thank you

 

[mdc1990zr1]

Hi Chan, I’m going trough the same stuff and maybe you can help resolving this mistery. My mechanic got done the job today and replaced lifters, timing components, he said cam shaft was good. Replaced oil pump just because of all the hard parts that he found in engine oil pan. So now there is a light on for misfire. He will try swapping the coils and see if that would do. Please let me know if you get to the bottom of that. Thank you

I look at cam and lifters like ring and pinion. If you need to replace one, you have to do both.

 

[EdGs]

@henriviera, if a lifter roller is locked up/chewed up, so is your cam, 100% guaranteed.

Did your mechanic pull the vvt solenoid and check for metal on the screens?