Cel Help: How fix P0505 and P0420?

[Kaviq89]

i got these codes don't know what to do, p0505, p0420??

 

[96swpdEK]

P0505 Idle Control System Malfunction

Basically you need to check all the sensors that run to the PCM (vehicle speed sensor, coolant temp sensor, air conditioning sensors, power steering pressure sensor, etc.) because the PCM adjusts the idle based on the info it receives from these sensors. You can do visual checks on the sensors to check for damage or corrosion. But make sure you check for vacuum leaks too.

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

http://www.obd-codes.com/p0420

all info found with help from GOOGLE in about 5 mins

 

[purpej1]

holla at ronj his sig has the list somewhere

 

[RonJ]

P0505:
Do you have a high or surging idle?

P0420:
This code generally means the catalytic converter is toast, though you should first rule out an exhaust leak before replacing it.