2004 Cavalier 2.2, once summer hit I started to get the PO496 code. It usually comes on instantly on start up on a warm day. It was strange in the spring if it was a colder day it would not come back on after cleared, only on warmer days. When the engine light is on the car smells like fuel. So far I have cleaned the purge solenoid with sea foam, but I don't think it helped any. And I have cleaned the gas cap today. Should I replace the purge solenoid and are they expensive? Or should I be looking for something else. Thanks!


One other issue I have noticed is that the car shakes a lot when in reverse (its an auto), is this normal. Everything seems to work and shift fine it just shakes.

 

this dtc will set when there is unwanted vacuum detected in the fuel tank. This is most likely caused by a faulty purge solenoid that does not seal. typically, this can also cause hard starts after fuel fill-ups.


remove the vent line from the purge solenoid. blow into the solenoid. You should not be able to blow through it. If you can, replace it.

 

Okay thanks, I never tried that when I had it apart.