My truck lit the check engine light 4 days ago....P042E EGR valve stuck open. I removed the EGR valve/solenoid and cleaned the plunger with carb cleaner. I also cleaned the cylinder that it pushes into. It wasn't terribly dirty but I did notice the plunger was out and it pushed back into place as I was wiping it down. Afterwards I went to Autozone and had them clear the code. It's been 4 days and no check engine light, so I assume that fixed it. There was only 1 metal gasket which I reused. Where do the other gaskets go?