2005 Prius - replacing catalytic converter at 85,000 miles

[omgitsroy326]

cat clogged at 85k on a prius which uses motor half the time.... i'm going to have to call BS on this one... i really doubt that it's your cat... anyhow if it's your cat.. there are exhaust stores that will replace it for less than 300 ....

I'd go with O2 sensor before your cat... 98percent sure it's not your cat... unless you got a rat suck in there = )

[richard schumacher]

What, nobody likes the failing 12V battery suggestion? We've seen many cases in which the low voltage of a failing 12V battery in a car of this age causes the computers to report random, intermittent, and false errors. It would be a mistake to buy a new cat before eliminating a much simpler and cheaper possibility.

Toto, it kinda sounds like you should get a second opinion from another Toyota dealer.

[dogfriend]

Originally Posted by richard schumacher

What, nobody likes the failing 12V battery suggestion?

If the tech is following the troubleshooting procedure, they are supposed to verify the battery voltage as one of the initial steps.

Also, the P0402 test is only run when certain conditions are satisfied; one of those conditions is a minimum battery voltage. So, it doesn't seem likely to get the P0402 code from a failing battery.

The other codes could be related to a flakey battery.

[galaxee]

the other codes are normal things that happen in day to day operations. ie, you press start button without sks present (or not detected.) you see these on a very regular basis but they do not kick a cel. they are not indicative of a problem including low 12v.

the reason DH is fairly sure that the problem is indeed the cat is:
1. she had a fuel injector cleaner run through the system recently.
2. dealership didn't even have to be asked to step up and offer part of the cost.

first things first, efi cleaners are usually linked to premature cat failures in a prius. since the engine does not normally run while the car just sits like other cars, the tech will commonly just stomp on the gas pedal to run the cleaner through. this overheats and melts the catalyst, leading to imminent failure.

secondly, the part is indeed about $1500. do you think the dealer would offer to eat half that cost UP FRONT if they weren't fairly certain that the problem was that expensive part, or that they probably had some causative role in the failure? remember this is not warranty- this comes right out of their profits. also, she could probably push them a little and get them to eat the entire part cost since they are in damage-control mode.

there are no other codes related to failures in the A/F sensor or O2 sensor present in this situation. DH has never, ever seen a P0420 without other related codes, that wasn't a cat. take that how you will.

if you want i can bring him back to the topic tonight when he gets home, but he's said what he has to say and it's not like this is something he hasn't gone through before.

[dogfriend]

So the moral of the story is don't let the shop talk you into a fuel injector cleaning unless you are actually having issues related to dirty fuel injectors. Which you probably won't have unless you are using bad gas (gas which doesn't have a good detergent package).

[galaxee]

Originally Posted by dogfriend

So the moral of the story is don't let the shop talk you into a fuel injector cleaning unless you are actually having issues related to dirty fuel injectors. Which you probably won't have unless you are using bad gas (gas which doesn't have a good detergent package).

hence the warning in What services you need and what you don't:
"since it doesn't idle, most techs will get in and stomp on the gas pedal until the EFI cleaner runs its course. this leads to a condition called "blinky check engine light" which means that you have overheated your catalyst and are in serious danger of melting the insides of your catalytic converter."

["toto princess"]

Thanks again for all of the information!

The light was off again today, so I managed to get my car inspected, which takes a little of the pressure off. I know I have to get the problem taken care of, but at least I don't have to worry about getting a ticket in the meantime. The dealer still hasn't called me to say the part is in. Now, with the holiday, it will be next week, at least.

I may end up getting a second opinion from another place, but what Galaxee says about the dealer totally makes since. All along it has been the dealer's behavior that has made me uncomfortable. If they feel guilty about the fuel injector cleaning, that would explain it.

They were so quick to offer half, and initially I was grateful (and still in shock!) Then the customer service guy wanted me to meet his boss so I could "thank her in person". She looked very uncomfortable and mumbled something about $1,500 being "a lot to pay at one time" and couldn't get out the door fast enough. It was very strange.

So, I have learned a lot already, thanks to all of your input. I will print out the list of necessary maintenance for future reference and avoid all of the other crap. I knew some of what I was getting was overkill, but never thought it would cause harm. And I will pay a lot more attention to what they are doing and ask a lot more questions. I will keep you posted about what happens next.

Thanks again!

["toto princess"]

By the way, if it is my catalytic converter, do I need to limit/stop driving even if the light isn't on? The customer service guy said it was fine to drive until they replaced it...

[galaxee]

yeah, you can keep driving it. your emissions are higher, but it won't hurt the drivetrain any.

[OrlandoGuy]

OK..This raises a question....with E10 fuel....I was under the impression that one of the benefits of E10 is that it cleans the injectors as a byproduct of being used. Is this right? If this is the case, why ever do an injector cleaning service?