Anytime the battery is disconnected, stored operating parameters may be lost from the PCM causing the engine to run rough for sometime while the PCM relearns the information. A battery cannot be accurately tested until it is at or near a fully charged state. Disconnect the negative
Battery Cable, then the positive cable from the battery and perform the following tests: Battery state of charge test, Open voltage circuit test, Battery load test, and Battery drain test. If you are replacing the battery, make sure you replace it with a battery with the identical dimensions, amperage rating, cold cranking rating, etc. Always disconnect the negative cable first and hook it up last or the battery may be shorted by the tool being used to loosen the cable clamps. Disconnect the negative battery cable, then the positive cable from the battery. Remove the battery hold-down clamp. Lift out the battery. Be careful - it's heavy. While the battery is out, inspect the battery tray for corrosion. If corrosion exists on the battery tray, detach the bolts and remove the tray from the engine compartment. Clean the deposits from the metal underneath the tray to prevent further corrosion. Installation is the reverse of removal.