I replaced the starter on my 2001 Honda civic lx the battery is good and the car won't start what should I DO NEXT The battery was tested all of the electrical systems are go. When tapping on the starter with a wrench twice it acted like it was going to start but cut off.

If tapping on the starter (not recommended) seemed to 'wake it up' then there may be a faulty connection within the starter.
Make certain that both ends of both battery cables are clean and tight. If you can, have the system tested for voltage drop. This test will verify that all available power is reaching the starter.

. Test all under hood and under dash fuses with a test light or multi-meter.

. Remove and fully charge the battery, clean the battery terminals and cable connections, and ensure the connections are tight. Most auto parts stores will test and charge batteries for free. Afterwards, remove the negative battery cable and clean the starter motor connections--ensure the crimp faces outward.

. Perform an ignition bypass test, where you connect a 12 AWG wire, or remote starter switch, from the positive battery cable to the "S" terminal on the starter motor solenoid. If the starter motor cranks, the problem is with the ignition switch, neutral safety switch, or wiring. If the starter motor doesn't crank, replace the starter motor solenoid--most of the time, the starter motor itself is fine.

The contacts within the solenoid get badly pitted, over time. Tapping on the solenoid may momentarily get you a better contact. It may serve as a "tell" that the solenoid is bad.