Intermittent noise at start up, not just the typical rattle (1 Viewer)

[cbpeck]

Hi guys, I have a '97 with 250k miles. It has the same startup rattle that every other 1fz has, presumably from the timing chain tensioner. In addition, it sometimes makes an additional noise that I'd describe as more of a knocking or clanking. It's inconsistent, and makes the noise once or twice every few seconds. I've noticed it at cold start ups, but not every cold start up. It sounds like it's coming from under the hood and outside of the engine. I've wondered about the belt tensioner, but that doesn't seem logical because the sound stops once it's warmed up.

I'll try to post a video, but the last time I started it hoping to record the noise it didn't do it, of course.

Any ideas about what the noise may be? Thanks in advance.

 

[SUMMIT CRUISERS]

If you haven't installed the ford filter adapter it definitely is worth a shot. It solved the cold startup rattle on my son's 94 a few years back. Here's a link: Rattle on start up

 

[plfj40]

I have a viscosity clutch bearing noise on my 95 when cold. It goes away when warm. Its attached to the engine fan.

 

[plfj40]

Try to spin the fan by hand and see if u can hear any bearing noise