2003 Grand cherokee 4.7 overheated, shut down no check engine or protection light inactive codes. Let car cool and ran like crap no water in oil no pressure in cooling system . Compression check 140psi in all but one. Rightside rear 45 psi, removed valve cover that hole exhaust valve rocker laying inside head,no damage to cam or rocker, so ok iguess ill pull the head, possible vave problem, remove all the junk needed to remove head, removed l/s valve cover exhaust valve on first hole cam out, someone please help. Thank You, Nate