The factory service manual doesn't state how much pressure to apply to the tensioner itself, just says "apply pressure" and then tighten the bottom adjustment bolt before tightening the top one. It doesn't need too much, just enough to seat the belt in the cam gear enough. Usually letting a new spring in the tensioner apply the pressure is enough.

As far as hesitation, what are your plug gaps set at?? Also might be a good idea to check the resistance range of your coolant temperature sensor, it is a 2 prong sensor in the manifold, should be near the thermostat housing. The resistance at near operating temperature (176F) should be 300ohms. You can test it while it's installed, no need to remove it, just unplug the connector which should have a rubber boot over it. If the ECU is not getting the correct readings, the fuel mixture will not be correct.

Here's the readings you should be getting:
32F 5.9K ohms
68F 2.5K ohms
104F 1.1K ohms
176F 300 ohms

Your local auto store should be able to get a replacement sensor, or they will likely be in stock. Rockauto has them, part # TX32 (Standard brand), this part number should cross reference at a parts store. I highly suggest staying away from the Wells brand sensor, as they are usually junk. Also, make sure to not get one for the gauge in automatic cars/trucks as they are a two prong as well.

-Robert