low compression cylinder #2
 

I have a 92 with a 3.0L V6. I just bought it a month ago and it didn't seem to be well maintained. I replaced the exhaust, cap, rotor, plugs, wires, timing belt, and water pump. The pickup has exactly 200,000 miles. After doing all of this it still didn't seem to run quite 100% so i did a compression test and cylinder #2 was reading 40psi. Do you think it could just be that the valves need adjusted or reshimmed? I am new to toyotas so i thought i would get some opinions. Thanks

It may well be that you will find that there is little, or no, valve clearance on your weak cylinder.

It is not likely though, that restoring the valve lash would restore the compression.

As the lash diminishes, the valve loses its ability to seat long enough to cool, and then it burns.

Most likely, only a valve grind job will restore your weak cylinder.