I took my truck to a local auto repair shop after it started misfiring. I was informed that my truck needed new spark plugs, ignition wires, distributor cap, rotor, and a few other items to correct the problem. I received an estimate of $281.00 and approved the work to be done. In the course of the repair the mechanic noticed many of my vacuum lines were old, cracked, and leaking. I was told that they could all be replaced for an additional $100.00. I agreed to that as well. Two weeks later I get a call saying that my truck is ready. The owner says there is still a problem but he put a special chemical in it that might fix it. He said if it didn't it would probably need valve work. Bottom line is after two weeks and almost $400 my truck runs EXACTLY the same as when I dropped it off!!