Rattling from engine bay (4.0L engine)

I really don’t think it’s any spun bearings or anything nearly that serious. I think it’s a bit of pre detonation that’s what I meant by spark knock, but even if it isn’t you’re right I might as well replace them

 

Any idea what it can be? Sounds like the same issue i’m having.

 

I recently had this issue. Truck started ticking on acceleration at low rpm and getting progressively worse.
First thought it was an exhaust leak or heat shields, couldn't find any issues there. Went to change the spark plugs and found oil on one of the spark plugs on the front cylinder, passenger side. I also had a small oil leak from the front corner of the passenger side valve cover that I thought wasn't a big deal.
Turns out the oil was leaking on the inside as well, down into the spark plug tube, onto the spark plug causing the issues. Replaced valve covers & spark plug tube seals, no more oil leaking onto spark plug. Problem fixed.
So, if you have a valve cover leak and a loud ticking sounds there is a good chance they're related. Hope this helps.

 

thats the 1GRFE trying to communicate to you in its native language

 

Thanks for the reply. I did my spark plugs about a month ago and noticed there was some oil leaking from on of the tube seals, it wasn’t very much at all so I figured it wasn’t an issue yet. Maybe I should change the valve cover gaskets and see if it helps. The oil leaking is on the same side as I hear the noise

 

Did you do it yourself or get a shop to do it?

 

Did it myself. Took about 4 hours, replaced the parts with OEM from Toyota.

 

I probably will have to try this then. Been chasing this noise since I got the truck 2 years ago and it’s been driving me crazy. 140$ from Toyota doesn’t sound too bad for the gasket

 

Did you have any misfires or check engine lights before doing this? Or just the ticking and a leak?

 

No misfires or lights, just the ticking and leak. Didn't think they were related until I found oil on the plug. Oil was causing pre-detonation which was making the noise.