Note. For circuit reference, see WIRING DIAGRAMS - 4.3L article.
Circuit Description
Fuel tank pressure sensor responds to changes in fuel tank pressure (or vacuum). Vacuum is considered negative pressure. This information is used in order to detect vacuum decay or an excessive vacuum during EVAP diagnostic routine.
Fuel tank pressure sensor signal voltage to VCM varies from a minimum of about 0.1 volt with pressure in fuel tank to greater than 4.0 volts with high vacuum in fuel tank.
Conditions for setting DTC
- Fuel tank pressure sensor voltage is less than 0.1 volt for greater than 5 seconds.