4.0L excessive lifter tick, high idle and rough time starting when cold.
Hi everyone, and happy labor day!
The 4.0L in my '02 JGC, which was purchased December 2012, is acting funny when cold.
During the first oil change, I noticed that the old oil was pretty thick and black, so I've been worrying that either oil was left in the engine for an excessive period of time, or that thick oil was purposely used to cover up an issue.
I've done two oil changes so far, the second with better results. The first one, in March '13, was with Rotella T5 10w-30. Pretty loud lifter tick, which didn't exist before the oil change, and after a week, pretty long period of time before the engine would turn over(talking like 3 seconds). When I decided to change the oil around a month later, with Valvoline Maxlife Nextgen, the Rotella that came out was almost completely opaque. Since putting in the Valvoline, the lifter tick has been slightly quieter, but the 4.0 is still just as difficult to start up under 50 degrees. Never had an instance where the engine wouldn't start up, but it still takes 3-4 seconds to do so. I can take a video of both the cold start up and the lifter tick if you'd like.
Still have pretty minimal motor repair experience, but since summer is coming up, I'd be willing to try an extensive repair myself if need be. Would like to get the motor fixed asap considering how good condition the rest of the vehicle is for having 116,000 miles. Thanks guys, and happy labor day.