You could pull engine evap valve and apply voltage see if it closes or opens depending on what it’s does naturally. If it’s stuck no difference with voltage applied it’s defective!
So he pressurized system looked at tank pressure valve to see if it was reading what he was doing externally. So he basically trouble shoot half of the evap circuit. Eliminating from engine purge valve from his hook up.
MAIC,excellent info and very easy to understand one qusetion when u checket the system with both test light hocked did u hocked both test light to singnal side on both purge and vent valve [ back probed] and other leds to battery plus if yes this well not harm the pcm.thanks for sharing always learn some thing from you my friend cheeeeeers
j georges good question. The answer is no. The test light uses very low amperage, plus the driver that actuates those solenoids “valves” is made to support it. It all depends what you are testing. A solenoid, valves and so, the computer driver is strong. Don’t use this method with sensor signal.
I was wondering were in va are you located I just got a 2003 hyundai tiburon gt 2.7 with a bad misfire a friend hooked up a scanner to it and it showed p1167 I have already installed new plugs and wires and a new coil pack would the o2 sensor cause the car to run rough or is it something else I got the car for my daughter and would like to get it running for her . I don't want to keep replacing parts that don't need to be I sure could use some help thanks . George Dickson. Oh i to live in va