Toyota Repair: 1985 Toyota Truck 22-R, 2.4L, 2 wheel drive, steel spacers, plastic spacers

Question
I have had my truck since it was new, now has 196,000 miles.  It is making a tapping noise and has lost power lately.  The tapping seems to go along with the rev of the engine.  Trip to dealer said it needed upper engine clean and new spark plugs for carbon buildup.  That did not help.  Wonder if it needs a valve adj or has exhaust problem.  Dealer sd it also needed a new "center link".  The idler arm connection looks like it is missing an inch wide washer to firm up the connection to the center link.  Trying to fix up truck for sons but dont want to dump money into it if has major problems.  Pls help.

Thanks.  Really like the old truck and would like to run it a few more years.

Answer
The valve train/rocker arms should be inspected, the valve clearance should be checked and adjusted, some of these engines used a couple of plastic spacers on the rocker arm shafts and they tend to wear causing misalignmet of the rocker arms, there are steel spacers available from the toyota dealer that addresses this condition.