replacing 4.6 plug wires

[747driver]

I have a code 420 on my 03 awd mounty. Which reads right bank catalyst system bad. I want to replace all my ignition coil wires...anybody have thoughts on what to replace with ? OEM,Bosch ? Would changing a 02 sensor be cheaper than replacing the whole cat system ?

Thanks

Chuck

 

[matt0248]

P0420 will not be caused be a bad coil pack/coil boot. It is almost always a failed/degraded catalytic converter. Yes trying to replace BOTH o2's is a lot cheaper than replacing converters. It is always worth a shot, but I would not get your hopes up.

 

[747driver]

No I wasn't changing the coil wires due to the 420 code. The car misses and runs rough at times so I thought it was time to change out the wires. I have 160,000 miles on it. Think I will pull out the o2 sensors and have a look at them.

 

[Steina]

160,000 miles on original plugs?