1999 Tacoma 2.7... Low compression

I just bought a 1999 Tacoma with 150k on it... Check engine light was on and it was missing/rough idle and a bit low on power.... Throwing code missing on cylinder #1... I changed plugs and wires and coil pack..... I did a compression test #1 was at 75lbs.. 2-4 were all above 175lbs... I added a bit of oil on top of piston #1 and redid compression test and it went up to 90lbs... In anyone's opinion does this indicate bad rings on cylinder #1 or could it still be valve or head gasket??? The rest of the truck is in great condition. I bought it knowing I might need a motor and if it does I am going to have a new motor put in it... Thanks for any help.. Dave

 

Bad rings or a sticking valve.

 

Could be a burnt exhaust valve. I suspect the head will have to come off at a minimum.

 

If compression goes up after adding oil it's the rings/cylinder wall.

I would pull the head off and have a look.