Can someone lead me in the right direction please. I have a 2005 Suburban LT with the 5.3 V8 with 4x4. I have issues with the evap system on the vehicle. I have replaced the gas cap several times, the purge valve solenoid by the tank, the solenoid on top of the intake and I still get the P0496 code kicking out. I can reset the code and it will stay off for about a week then it lights up again. Sometimes I have issues with it taking fuel. Almost like the roll over valve is closed on it. Sometimes it will take fuel just fine, and then while filling it up, it will spit out some excess fuel in the fill tube. Can someone point me to the right direction. thanks.




Patrick

You've replaced solenoids I would have troubleshot. Your symptoms combined with it spitting out fuel when you fill it make me wonder about the tank-vent path. Perhaps it is plugged?

I'm unfamiliar with your driving habits such as miles per day, number of trips, how warmed-up your car gets, etc. Could you elaborate on what your car sees between resetting the code and then MIL lighting up again about a week later?

Also, I wonder if you reset then drive a time or two then scan again and see if you have a pending code.

It gets driven perhaps 30 miles a day pending on how much running around needs to get done. My wife is the primary driver and she drives easy, I have a little bit heavy foot so I am more aggressive. The only code that comes up every time is the P0496, nothing else. Every time I would replace a part to see if it was the fix, I always reset the computer, the longest is lasted was a month, then it came back on again.

Here is some more information about the P0496 and some trouble shooting info..
http://www.obd-codes.com/p0496

Cool, clearer picture. I'm guessing that after a couple of cycles of it seeing the problem it stores a pending code for the issue and waits for the issue to continue long enough to light the light. I'd say check for pending codes at the end of each day when it gets back home. Goal here is to identify more closely if the issue is intermittent or if it returns immediately and waits to tell you about it.