DWW:
Those codes indicate an issue with the MDS solenoid on cyl #4. At 163K, you might have an issue with the solenoid, or the oil supply to it. Worse case IMO, would be the beginning of the dreaded lifter failure. Hopefully that is the not the case here. If by chance you do have a failing lifter, you would want to get in there, and replace them all before serious damage sets in. If the lifter(s) start to fail, they will take out the cam, and in time, the engine.

Don

 

I realize I will probably have to get a diagnostic done but simply replacing the lifters solves the issue?

 

If that is your issue, and you catch it early enough, yes. You will want to look into it a bit further tho, so you know that is the issue. The lifters are not cheap, and since the heads must some off, labor, unless you can DIY, and be quite a shock. Folks who need a cam and lifters, are paying $3.5-$4k for this repair. It may be just a failing solenoid. They are ~$80,. The intake must come off to access them.

Don

 

Just a quick update. My mechanic confirmed, misfire in cylinder 4 but also got a code stating wrong engine oil or something to that effect? Regardless, he replaced both plugs in #4 and that squared away the misfire. I got it back and replaced the rest of the plugs. Have put about 250 miles on it since, all codes have cleared. New set of plugs really put some pep in her step! The code about the engine oil I found odd. It has less than 5000 miles on this change running full synthetic. Mechanic mentioned it could possibly be an oil pressure switch?

 

What weight oil are you running?

 

How many miles on the old set of plugs? The spec for the oem plugs is 30k. You can run them a bit longer, but I would not exceed 50k. If they were very worn, that explains the restored pep.

Don

 

Ashamed to say this is the first set of plugs for me. I am the second owner, purchased with 66000 miles on it. I have run 5w20 full synthetic since buying it.

 

Holy cow! I'm surprised you didn't have issues earlier. I bought my 2006 in 2011 it only had 22k miles, I kept it until 2020 when it had 150k miles and I personally did 4 spark plug changes. I'm sure it is still running strong somewhere and hopefully the next owner has done the 5th change.