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Stock Pentastar 3.6l VVT Lag (Fixed)
I wanted to share a VVT issue I had and what worked for me to resolve it. I have a 2012 Wrangler Pentastar 3.6L NAG1 with 215K on it. I have only owned it for a few months and it is my first dealing with the pentastar engine, but I have done some heavy research (crash course style)
Idles and drives great. CEL came on one time and gave a P0018 code, but still ran fine. Came on another day with P0018 and P0016 but ran fine. It did die once when idling through a parking lot right when pulling in to a parking spot. I was not logging that day so didn't see exactly what happened though.
After replacing a VVT valve on my 2013 Cadillac SRX High Feature 3.6L (had it a few months now too), I decided to log the cam timing on this jeep and look for a similar issue. I found the same exact problem the Cadillac had but looked worse on the jeep log. The computer would command 0%DC to drop VVT back to retarded but the cam timing would lag coming into position. Especially the exhaust cams, probably because they are adjusted very often. The exhaust phasers also have a clock spring in them to return them for startup, and the engine always starts nice.
After some research I felt it was probably the Oil Control Valves which torque at 110ft lbs on the front of each cam, holding on the phaser with timing chain sprocket. Sure I could swap the valve cover mounted solenoids around first, to make sure it is not them. I looked for some videos to see how difficult it would be to swap the OCV's. I then ran across a Snap-On video showing how to use the VVT cleaning function on the scan tool.
I then plugged in my wiTech Mopar clone and found the same cleaning function. I went through this function twice and you can see on the log, it cleaned up very nicely. Still in the future I may have to replace the OCV's or solenoids, but this was a great feature and so far so good. I did not notice the cleaning function on the VCM Scanner, but it may be there somewhere.
Dealing with this on the GM High Feature V6 and now on the Pentastar V6, I will log cam timing as a routine maintenance item on DOHC VVT's, much like reviewing LTFT's as a maintenance inspection task.
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