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its been forever since i worked on one of these. i thought i had a bad purge valve because i couldnt pull a vacuum on the system according to the scanner. fuel tank pressure sensor stays at 1.5 volts. smoke it no leaks with vent vlave closed. fuel tank pressure sensor stays at 1.5 volts even with smoke machine on system. hear purge click no vacuum coming out of it at idle. find no vacuum from hose that goes on throttle body at idle. its ported vacuum? anyone remember back that far? i even closed vent valve puilled strong vacuum on system from an intake source. so now im thinking i have a stuck fuel tank pressure sensor. sound like thats the issue?
Definitely sounds like the sensor is stuck. Should have started reading lower voltage with the smoke machine on the system, especially if you got the flow gauge to show zero. Sensor time!
As for the vacuum source for the purge valve... I have no idea. :lol: Most of these trucks that came into my bay had bigger problems, like blown head gaskets and smoked wheel bearings.
That’s what I was thinking especially when I stole vacuum from the brake booster and closed the vent valve was expecting to see a huge voltage spike in a very short time. Had to bust out the old antique tech 2 since snap on had no purge and seal option
Not that I encourage parts changing, but I might just put a TPS on it. :silly: I chased the same code on an Isuzu Hombre (rebadged Jimmy/Sonoma) for three days before I just gave in and replaced it.
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