P0420 means that the bank 1 second o2 sensor is detecting a poor catalytic converter. And you should have the catalytic converter and exhaust components checked, if that is all good then replace the o2 sensor after the catalytic converter on the side of the engine that has the #1 cylinder.
P0430 is the exact same as the one before only it is on the other exhast pipe after the catalytic converter.
P0171 means system on bank one is lean- The MAF (Mass Air Flow) Sensor is dirty or faulty or there is a vaccum leak.
And the p0174 is the exact same as the one above only its the bank 2.
So if I were you I would check the MAF sensor and see if the codes come back. If so check for a vaccum leak. They could be related or the P04's and the p01's could be completely not related.
Wednesday, December 26th, 2007 AT 3:22 PM