Miss, low compression, and no problem found.

THis is an 86 CIvic wagon, 1.5, auto.
I bought a used engine. It run's but has low compression on #1.
So I pulled it out, and removed the Head, and took it to the Automotive machinest.
He pulled all the valves. He found no reason for the miss or the low compression. Now I'm stumped and a little afraid to put it all back togather again.
The machinest says he had another head given to him that had the same problem. The other customer finally bought a Head from another engine and it worked.
Who has some ideas on this one?
Soon please!

UPDATE
I got the engine started tonite. It sounds fine. No miss.
But now I have a plethora of problems with the Spaghetti of Vacuam tubing.
I cant get the engine to idle.
It looks like I did not need that sensor in the back of the engine.

The fan will do fine if I jump the hot wire to the fan connection. It wont start on it's own. I dont know where that 'Fan Relay' is either.

any help would be so appreciated.

the fan should be fine i have my 86 hard wired to always stay on the hoes should have colors on the hoes and on the place it goes if not match what you can and i will see if i can get a diagram for you