1HZ HZJ73 Rattle on Cold Start

[needmoney4gas]

Experiencing a high pitched rattle on cold starts on my 1991 HZJ73. Approaching 300,000 miles on the odometer. Started noticing about a week ago. Timing does not line up with any recent work performed.

Here’s a video I recorded yesterday:


Rattle stops after 5 seconds or so as in the video. Only happens on a dead cold start. If I turn off engine and let sit for 30 mins, the rattle does not get reproduced. My first thought was an oil issue upon start up, so I swapped out the oil filter (oem) with new oem and checked oil level. Both seem fine. Still rattling on a cold start after sitting overnight.

Any ideas/advice on how to diagnose? Thanks in advance for any help.

 

[Croe]

Ouch.
I would have said it sounds like a lifter bleeding down when sitting. Except I have no clue what sort of lifters are in these. I did find one post about an HZ in a FJ 80 that was making a noise upon start up, and it was a possible injector issues. Does yours smoke at start up when making the noise?
Good Luck