So I have a 2004 Ford Explorer 4.0L v6.
I got it for a steal because it needed some work.
95k miles.
It had a tick/rattle that was assumed to be the timing chain as is notorious for this engine. All timing chain parts and tensioner etc have been replaced and so have the oil pump and pickup tube assembly. It has a very audible tick that gets worse as it is driven and goes under load. The tick is very rhythmic with the RPMs. I use a listening stick. A long skinny peice of rebar held to my ear and touch it to places to narrow it down. It no longer is giving me any noise when touched to the timing chain covers or tensioners. So I dont think this tick is timing chain. I touch it to the back of the driver's side head and I hear it clear as day, as if its being played into headphones on my ear. So I thought it could be a rod knock. I saw a video where someone diagnosed rod knock by listening and disconnecting the spark plug wire from the distributor while its running. When he pulled the one that was knocking, the tick went away. I tried this and it makes zero difference. I am not getting any trouble codes either.
I will be selling this vehicle and really need to get what I can out of it. So short of a rebuild or other major repairs, if I can fix this tick it would be great.
Any ideas? Could it still be a rod knock even if that cylinder is disconnected from the distributor? Is there anything simpler that could be causing it?
Thank you much!