This morning when I started my '08 gen 4, the engine started with no problem BUT the check engine light came on. The slip indicator and VSC off lights were also blinking. I hooked up my bluetooth OBDII and got a reading of P0456.

I googled the code and the first hit I read talked about a small leak in the evap system. I did the ol' "check the gas cap" thing and tightened it another click - although it wasn't really that loose.

My question for this distinguished group of talented and knowledgeable folks is this: I've had the check engine light on once or twice for very minor stuff since I got the truck last June but NOT with the slip indicator and VSC Off lights on.

Any thoughts?

POST EDIT: Interestingly, and a little scarily, a couple of photos/screen shots popped up on my computer screen under my post, after I posted it, with links to discussions on this very topic!

Small evap leak is typically gas cap. Did you clear the codes? If it comes back on you can try replacing the gas cap or go in for actual diagnosis. Might have to smoke it. But... clear and see if it comes back after clicking the cap.

Also... Code P0456 - When its not the gas cap

Yep, I had same thing with my '08 back in November.
Get a replacement fuel cap and then reset the code.
No problems since....

I forgot to mention, I replaced my cap yesterday. Just waiting to see if clears up my evap concern. lol. I’d get all the lights, but none flashing. Didn’t ask what codes I had though.

Amazingly enough, it turned out to be the gas cap! (I say amazingly not because your advice turned out to be correct but rather because it is rarely my luck to have a problem end up being so cheap and easy to fix!)

I've gotten the old "gas cap is loose" fix suggested many times over the years regarding different problems with different vehicles - and this is the first time it really WAS a loose gas cap!

I read on another thread that the way to find out if the cap is a problem was to tighten it and check it awhile later to see if it could be turned to the left with little or no resistance. When I did that, and it was in fact loose, I realized that I had noticed the last few fill-ups that the cap was loose and was basically just sitting there. Once I even remembered thinking that it was odd and I was a little upset with myself for not tightening it!

Thanks to everyone for your help!

Glad it was simple. So far, so good on my new cap solving my evap issue.