Question

Fuel volume regulator circuit open 2003 Toyota Tacoma 2.4L, I replaced fuel filter

Answer 1

This code is not valid for this vehicle, The way a scan tool works is that it store code definition in its library and as it make a connection with the vehicle DLC it becomes a host, there it communicates and matches the code that is set in the vehicles ECM and displays the code that it has matched to the vehicles ECM.This code that you have is not valid, Recheck the code and if possible use a different scan tool, When P0001 is found and your vehicle is most likely will be a lean code, If it is a lean code you may want to do a MAF cleaning .

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