Q&A

My mounty is throwing codes for 4 adjacent cylinders 1,2,3,and 4... The truck runs great when moving, but shakes at idle... its misfiring in all cylinders... had compression test done, and the cylinders are random from 120-170psi.. Uptown auto says they believe its my timing, and I need to replace all my timing components, but they can't tell unless the tear it down.. and that will be $1200 parts and labor... Is this the case, or something else? Im not sure what to do.. I dont want to spend 1200, and that not be the problem.. Thanks