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Sudden drop in rpm while driving

Lately while I am driving my 2001 Toyota Camry I feel my car pause while driving. When this occurs the driving rpm’s drop from ~2000-2500 rpm to ~1000. This generally occurs when I am accelerating but this is not always. Any ideas. My timing belt was replaced 6 months ago.

Possible dirty fuel filter or perhaps a weak fuel pump.

First check for stored fault codes. If the engine is suddenly dropping out there should be some.

The lst of possibilities is long, from intermittant fuel pressure loss (possible fuel pressure regulator problem) to intermittant spark loss (intermittant crank or cam sensor loss, intermittant MAP sensor loss, MAF sensor loss, etc.) to a baffle rusted free and intermittantly interfering with your exhaust flow.

I’m inclined to think the timing belt is irrelevant, because once a timing belt jumps a tooth it stays there. It doesn’t act intermittantly.