Gusset
11-14-2009, 02:49 AM
2000 Legacy Wagon, 117k, throwing a CEL code P0420. The used car dealer I purchased the car from has committed to getting any emissions issues taken care of as part of the purchase agreement.
The mechanic that did a pre-purchase inspection for me noticed an exhaust leak at the catalytic converter flange. A little research suggests that this is a potential cause for the OBDII code...most of the docs I found pretty much state that the first step in troubleshooting this code should be to check for exhaust leaks and fix them before bothering with anything else.
Dealer had the cat flange gaskets replaced, and the mechanic is confident that the leak has been eliminated. If the leak was indeed the root cause, and it's fixed, how long would it take for the code to clear and the CEL to be turned off?
Am I better off clearing the code and seeing if it comes back on, or am I better off leaving it along and waiting to see if it turns off? Which will be the quicker way to find out if the problem has been resolved?
Thanks!
The mechanic that did a pre-purchase inspection for me noticed an exhaust leak at the catalytic converter flange. A little research suggests that this is a potential cause for the OBDII code...most of the docs I found pretty much state that the first step in troubleshooting this code should be to check for exhaust leaks and fix them before bothering with anything else.
Dealer had the cat flange gaskets replaced, and the mechanic is confident that the leak has been eliminated. If the leak was indeed the root cause, and it's fixed, how long would it take for the code to clear and the CEL to be turned off?
Am I better off clearing the code and seeing if it comes back on, or am I better off leaving it along and waiting to see if it turns off? Which will be the quicker way to find out if the problem has been resolved?
Thanks!