Timing belt

I replaced my timing belt, water pump, idler pulleys, and tensioner on my 2003 tacoma, by setting the camshafts and crankcase to the proper positions and marking the old belt so I could transfer the marks to the new belt. Did that and when I placed new belt in these positions the marks would always be a few notches off. Put the old belt back on and the marks would line up fine. After wasting 2 hours trying to figure out why it was wrong I put the new belt on with all the slack on the tensioner side of belt and pulled the pin as camshafts and crank all in proper positions. Turned motor over by hand and everything lined up. Started engine and everything good. Any ideas as to why this happened? Thanks for any info

 

In my Subaru T belt experiences,
Once all 12 fucking marks line up…..
Then pin pulled, and hand cranking CS bolt 2 complete engine revolutions did the trick

 

Usually, the problem is your slack was wrong. You need all the slack at the tensioner or it'll let 1 part spin without pulling the part behind it.

 

The marks you see on the timing belt are absolutely, positively, completely and without a doubt, useless.