Check Engine Light -- 2001 Prius

I have a 2001 Prius and the 'check engine' light came on yesterday, about a day after filling the tank up. The tank was still on full. I'm NOT referring to the warning triangle that can come up on the main screen, but the engine light in the cluster.

On most cars, the 'check engine' light usually means an emissions or transmission problem. Most notably the light is triggered when filling the car with bad gasoline or leaving the gas cap off / having it on too loosely.

As with other cars, the definition of what this light means on the Prius is obscure in the manual. Is this light treated the same as other cars -- being an emissions problem -- or could there actually be something wrong with it?

The car is performing just as it has been, though as I said I did just fill it up with gas.

Toyota likes to charge $90 to run any diagnostic so I'd prefer to have a feel for what the problem is before I take it in and ask them.

 

I brought it in to a Toyota dealership and they are saying that the catalytic converter has gone, with a replacement costing $2100.

This seems kind of weird to me that it would go so quickly, one would expect a part like this to have a more gradual failure, barring physical damage or abuse.

The last few times I have taken either of my Toyotas to Toyota dealerships I haven't been very impressed, it seems to me that they just hook it up to their computer and don't do any real troubleshooting beyond that. Since I've seen this at multiple dealerships now I'm thinking this is what Toyota is telling them to do.

Anyway, I'm digressing. Assuming the more likely scenario of me just having a bad tank of gas, how long will it take for the 'check engine' light to clear?

 

I got a code from the dealership, I'm hoping this is the right diagnostic code and it will help someone here isolate this better:

P0420

 

So none of the techies here have any insight on this? Will a universal catalytic converter work on the Prius? What else could it be with this error code, as I think it's a safe assumption that the dealership didn't check a single thing?

 

Well if no one knows, and the check engine light doesn't disappear after a new tankful of gas or two, I'll just get a universal catalytic converter for it.

$100 vs. $2200 is a pretty huge difference.

Thanks for the direction.

 

Yes, you're not saying anything unknown by posting that.

However, the P0420 code isn't triggered by the CC itself, but it is instead triggered by trying to match whether or not the sensors in front of it and behind it are giving expected readings. So, of course, the problem could be the sensors. I'm hesitant to believe that the mechanic troubleshot anything. For a $2200 repair, of course I have to be shown by the mechanic who worked on the car exactly what he looked at. Toyota dealerships aren't set up to do this, however, customers are never face to face with any of the mechanics.

The real question is, how will a universal CC affect the Prius? I can tell you that there is a 0% chance that I am going to spend $2200+ tax on a catalytic converter when I can get one for $50 and a new set of universal sensors for another $50.

 

I thought about that, however since a new CC would go for $1700+ tax just for the part, one has to figure that a salvaged one would go for $600-$1000 (unless I have a friend who can hook me up, which I don't). That's still too much .... and of course who knows how long a salvaged part is going to last.

 

From what I gather, this is what we're looking at that can trigger this code:

- Leaks
- Physical Damage
- Bad Sensors
- The CC actually being bad

The Toyota dealership did their diagnosis but didn't explain to me what they checked, so I'm suspicious that they just looked at the error code. However, they want to replace two gaskets along with the CC, so if they did actually troubleshoot beyond the computer code it may be physically damaged or they found a leak. I will talk to them again tomorrow and hopefully get some better answers now that I will have better questions.

For future reference, it does appear that a universal CC will probably work on the Prius. If I go that route I will post the results, though, to be sure.

 

The HC absorber is a separate piece, from what I have been told. This is used to store vapors until the CC has warmed up and is only used for a couple of minutes after the car is started.

Even if the HC is bypassed altogether by a universal CC, at worst the Prius will be acting like a normal car as far as emissions goes.

 

Hm. It's too bad I can't get you to look at it. I'm not having much confidence in what I've seen so far with this issue locally.