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The FSM does not mention or show any diagram with a check valve so unless you are talking about the fuel pressure regulator in the fuel rail system, it must be internal to the pump.


Typically the check valve is in the outlet end of the fuel pump, but not always. There is also generally an overpressure relief valve in the pump as well.

Don't get too hung up on "factory service manual says", as it's published by humans, and is far from faultless or all encompassing.

'97 T-100 SR5
'86 Toyota's, the variety pack (all gone)