I have the same code. Luckily for me it happened a day or two after my last emission test so I have some time to fix it. The truck has been running good and I am not working so it will have to wait a little while. Let us know how it works out for you.

 

the shop i talked to does a flow test to test to see if the cats are beginning to clog. it has an appointment to go in beginning of next week.

i also talked to my mechanic and he said that that code means the cat is shot but im still gonna have the flow test done to confirm it. hes gonna get back to me for a quote on plug change, ebrake, and a fuel filter change.

 

I had the same problem with my truck.....had a serious misfire problem though that was solved with new plugs. Dealer didn't break any of them either which was a huge relief. Also got the cat replaced under the emissions warranty.

 

If the cat's not clogged, it's probably still bad - unless you have an exhaust leak between the cat and the sensor. That can also trip the code. All the system knows is the cat is not doing its job up to specs.

 

alright. thanks for all the help glc. the shop thats doing my plugs, ebrake, dents, fuel filter, and inspection gave me a price for the cat and it was 240. does that sound about right for a stock cat? i was thinking of maybe just having them delete the two rear cats and putting high flows in or something but it mostly depends on cost and whether or not the lack of cats will throw CELs.

 

A cat for $240? Installed? Jump on it. Most others are quoting over $1000 for cat replacement.

 

oh wow. well im not going with OEM replacement. Im gonna go highflow route and have my exhaust done at the same time. i didnt know that was such a good deal. thanks for the heads up.

 

If we're talking OEM cats its a great deal. I know aftermarket cats are cheaper, I'm just not real sure how much cheaper.

 

yeah. i got prices for highflows around 65 a cat and i have the 2-cat system so. i figured if i need to replace one and i wanna do my exhaust soon i will just have high flows put in. plus my mom is paying for my exhaust as my birthday gift.cant go wrong there

 

i got both cats flow tested yesterday and both are good as new. the truck is having the plugs and fuel filter changed today, ill being doing a new air filter, DWV mod, and oil change this weekend.

Other possible causes were COP, bad o2 sensor, or a vacuum leak. Any idea if the vacuum leak would cause this and any prominent places for me to check if the plugs dont fix it?

 

Have you ruled out any kind of exhaust leak? I suppose it could be a bad O2 sensor - and if so, what I'd do is replace the front sensors and move the fronts to the back.

 

I have a very similar problem, mine an 06 5.4L has 145,000. My injectors were stuck open, so I replace them, I had a miss so I replaced the plugs, and this fixed all my problems, other than my power. I think I ruined my cats with the faulty plugs and injectors, because my dual exhaust isn't loud at all and I have no power when I hit the throttle. Since the plugs and injectors and the Lisel tool put a dent in the wallet. I got a quote from a place in town to replace and install two cats with magnaflow for $225 will probably get this done on the next pay check. Hopefully this fixes it and I don't have to go chasing a vacuum problem.....

 

the gun runs very strong and doesnt stutter or hesitate so im not quite sure. that doesnt sound like it would have injectors stuck open or a vacuum leak cause wouldnt those make it run a little sluggish?

 

got the plugs and fuel filter swapped and truck is running great. CEL is gone and hasnt come back. truck is inspected and getting registered tomorrow and true duals are going on tuesday