2007 S-Type 100k miles

Pulled battery to reset parking brake and replaced with new spec battery. Might not be relevant but when reconnected new battery many codes and I thought they would reset after some driving and most did and the car drove well for two days.

Now runs rough and misfire 1,2,& 3 then 1 & 2 clear and now only misfire #3. I put new coils in this summer and they were cheap generic so maybe a coil went out but I'm also getting low voltage on bank 2 both oxygen sensors.

This make sense to anyone? Like some input before I strip down for coil replacement again.

 

Whoa, I say whoa! Keep your clothes on! Why you prefer to work in the nude makes no sense to me, but I don't judge.

Oh anyway, you've got brand new problems that only showed up after a battery change. As you stand there in the buff wondering why, I'd sure think it's related to the battery replacement. A few thoughts:

1) Charge the new battery. Connect it overnight to an automatic charger with at least a 10 amp output. Most batteries are not fully charged when purchased. You can't always count on the alternator to make up the deficit.

2) Check your charging system. On a 2003+, you should see about 14.5v right after engine start, settling down around 13.5v within a few minutes.

3) Clean the connection where the ground cable attaches to the body. This connection is prone to corrosion, especially in the "From" states that use lots of road salt. Could be during the battery replacement, this connection was disturbed when the cable was moved out of the way.

4) Please put a towel on the seat while working.

 

+1 on charging the battery at 5 to 10 amps overnight before replacing any parts.

Resist the desire to clear the DTCs as this also resets the monitors. This is especially important if the vehicle needs to pass a smog test in the near future.