Dejola <johnandjanet@gmail.com> wrote in news:1190904275.516534.123200
@g4g2000hsf.googlegroups.com:

The dealer will replace the cat with a new OEM one, which is why you're
quoted that figure. Aftermarket cats will be a third that.

Before you actually get it replaced though, read this, from Honda
ServiceNews from Oct '98:

Before you troubleshoot an OBD II vehicle that stores DTC P0420 catalyst
system efficiency below threshold), run these quick checks:
1. Check for a leak in the exhaust system. If you find one, repair it,
clear the DTC, and test-drive the vehicle.
If the DTC doesn’t come back, return the vehicle to the customer.
If the DTC returns, go to step 2.
2. Connect the PGM Tester, and test-drive the vehicle while an assistant
monitors the voltage signal from the secondary oxygen sensor (HO2S S2).
After the catalyst reaches operating temperature, the HO2S S2 voltage
should stay between 0.5 and 0.8 V at steady cruising speed. During  
deceleration, the voltage should be steady at 0.1 V or less.
If the voltage readings are OK, clear the DTC, and return the vehicle to
the customer.
At cruising speed, if the voltage fluctuates or stays below 5 V, go to
step 3.
3. Measure the inlet and outlet external temperatures of the catalytic
converter with a thermometer capable of reading up to 500°F.
If the outlet temperature is more than 100°F hotter than the inlet
temperature, the converter is OK; clear the DTC, and return the vehicle to
the customer.
If the outlet temperature is less than 100°F hotter than the inlet
temperature, replace the converter.

Two separate Honda dealers have diagnosed a failed catalytic converter
on my daughter's 2001 Honda CR/V. One wants $1,100 to fix it. The
other simply says, "Thousands." The catalytic converter needs to be
replaced. The car has 105,000 miles on it.

Can anyone give me an authorative real world estimate of what this
repair should cost, including if done by someone other than a dealer?

Thanks