Mmmmmm. . . . I love that stuff. Marvel Mystery Oil.
But I don't think MMO will help that knock... It almost sounds too loud for a valve lifter. More like a rod bearing or something. It needs a tear down to find out I think, or someone with a trained ear right there to diagnose it. If it is a lifter, it is a bad one. But 2005 is pretty old already.
No, really. Well, for certain things. We needed a lawn mower for up at the cabin. So I bought one at a garage sale for $25. The thing was only 4 years old but the guy used it to mow his vacant lot next door. The mower had never had the oil changed. Just added some. And the engine ran, but sputtered a lot. I drained the nasty old oil and I ran a 25/75 mixture of MMO and regular oil through the engine twice, emptying it after running the engine for 20 to 30 minutes each time. The second mixture came out looking much cleaner and I even mowed part of my yard for 30 minutes. A good cleaning of the outsides of the mower, sharpen the blade, adjust the carburetor linkage so that the throttle worked properly and it ran like new.
I've used it on any used car I bought for the kids or as a second car also. First thing, change the oil and use one half quart of MMO and 1/2 quart of 5w-30 for the last quart for the oil change. Run that for 1,500 miles or so and change the oil to 100% 5w-30. Cleans any gunk out of them. I used to add 8oz to a full tank of gas in all my new cars too for the first 1,500 miles as a top cylinder lube for break in. The engines always seemed to break in well and have more than average performance. I had several dealer techs tell say to me, "You got a good engine in there. It runs really smooth and has more pick up than the average (insert car model). I have not done so with the Equinox as I am not sure a DI engine would like anything other than fuel in the system. DI engines have enough "mystery" to them and need no more added. :beer:
Well. . . . my 2 cents while I drink my morning coffee. But, yeah, maybe some MMO might clear out the OPs knocking or "ticking". Half a quart in the crankcase with the oil might help. Don;t think it would hurt to try it.
