My EVAP cannister was bad last year and I let it go for a long time...I am sure running it with a bad EVAP clogged up the cat, let crap get stuck in there...

I replaced the O2 and the only other thing it can be, or likely be according to Yotatechers is a bad cat, I do have a very foul smell out of the rear of the truck, so I am betting, hoping this is the case.

I am lucky, that the cat along with my muffler is being had at a price that is affordable to me about $180 and my friend will bend up a new system for about $75.

I would be willing to bet your cat is the issue, I would check around some more before investing too much, maybe a local Toyota club has a contact at an exhaust shop that can help you out at a little better price...I would go for universal type high flow cats, should you have to replace another one.

 

Will a bad EVAP cannister throw it's own CEL code or throw a code at all? How did you know that yours was bad and how does it being bad affect the cats? Thanks.

Matt

 

Yes, an EVAP should throw it's own code.

https://www.yotatech.com/forums/f16/write-up-charcoal-cannister-flush-evap-p0441-check-engine-light-61907/
https://www.yotatech.com/forums/f16/vacuum-switching-valve-vsv-constantly-switch-tick-when-running-p0441-please-help-61152/

In BOSTON4RUNNER's case was more than likely a prolonged overly rich condition which likely led to converter failure, but in your case I am not sure the same applies. I wouldn't assume the two vehicles are in the same scenario.

 

MTL 4Runner,
Do you think I'm just the victim of high mileage and the efficiency has declined to a point that it's throwing the code? I've never gotten any other engine codes which makes me think it's high mileage. If I was running in a fuel rich condition, wouldn't there have been warning signs or CELs thrown? I've seen none of this.

What puzzles me is why it is showing up so much more frequently now. In the past, it may come on every 3-4 months and stay on for a week or two (maybe even shorter) but then would turn itself off. Does me clearing the codes with the OBD2 have something to do with it coming back so frequently? It's starting to get really aggravating and looks like it will be quite expensive to remedy.

Do you think a trip to Meineke would be worth it? Thanks for your help bro. Later.

Matt

 

It will definitely throw its own code, and like a silly willy I let it stay in the truck, I should have just replace it witha new one for 200 bucks,,,(the evap cannister and vsv valve) which I did buy new from the dealer eventually,,,in the meanwhile it killed the cat...

a pennywise, a dolllar foolish I was

save up, figure out what is wrong and fix it, so it doesnt lead to other problems..

I am kinda lucky, I build cars as a hobby, do restorations on muscle cars and have alot of contacts so when something goes wrong I am in a good situation.....I would be screwed in farming it all out..

I would suggest, take the time, make sure it is diagnosed right and any parts in question,,,replace them, will be a good opportunity to upgrade

 

the thing is now, maybe the car was a little inefficient, now had become clogged, full of crap or other label you want to throw on it....its efficiency has continued to decline,,,thus the more frequent codes

my EVAP did the same thing, once in awhile it came on,,,,it would go out for a month or two, then came on all the time, there were other signs, such as a foul smell out of the exhaust, I knew the emissions equipment was not working as it should,,,go to the point the light would come on every day or so, even after being reset.

worth a trip to Minekie or Midas? I think not, I would consult a local speed shop, get some low buck but good cats, have a nice custom system bent up with a free flow type muffler etc.....jusrt my opinion

 

Boston4Runner,
I know you said earlier that you were getting all of your stuff installed today. PLEASE post the results that you get on here (ie CEL goes out after you put the new high flow cat on) and keep us updated if the CEL comes back on anytime in the near future. Thanks.

Matt

 

Well, I called Meinke today and talked to one of their techs. Total waste of time. He said that if I was not experiencing any performance losses or changes in gas mileage, that it's probably not bad. He said the same thing though that some of ya'll have said....there's a strong chance that I could change both of them and the light come back on in a month or so, maybe sooner.

My question is this...if the rear O2 sensor was bad or failing, wouldn't it throw it's on code to the CEL instead of this catalyst code?

Looks like I'm going to be getting a lot of use out of this OBD2.

Matt

 

I may see about replacing my O2 sensors first and see what that does. I just don't think the catalyst has failed since I see no loss of performance or gas mileage. If that doesn't work, then I'll probably replace the rear cat with one of these and hope that the front isn't bad also...

http://www.walkerexhaust.com/product...iversalfit.asp

The Walker Ultra Catlaytic Converter. The tech rep said that even with the added "capability" of the converter, it was not any more restrictive than a stock converter and may even flow slightly more exhaust. It just has more precious metals in it so that it performs better. I don't want a high flow cat because I don't want to significantly change my exhaust note. This cat is made by the same company that makes Dynomax exhaust, and I've been very happy with my muffler. I don't know....we'll see where it goes. I imagine it will be at least $200 to replace the O2 sensors even if I do it myself.

Matt

 

Anyone know if our cats have an air tube connection?

Matt

 

No they do not.

Most 3-way cats don't have air injection.

 

Matt, notice that the walker cat is only 49 state legal so I bet you'll more than likely run into issues later. I suggest you look for one that is 50 state legal and make sure it is a 3-way converter.

Since your front sensor is an A/F sensor, that alone will run about $190 and the rear is a regular O2 so that will be about $90 from URD. I am afraid there is no cheap way to get this solved for you but the sensors would be a good start because at least then you'll be sure it is not a sensor error causing converter failure later.

 

MTL,
What reputable companies make a 3-way "regular flow" aftermarket cat? The reason I started looking into Walker is because they also make a "quiet flow" muffler, which is an aftermarket muffler that provides slightly higher flow than a stock muffler, but does not produce the sound of a Dynomax, MagnaFlow, etc. It seems that all of MagnaFlow's cats are "high flow" which would probably produce a noticeable change in my exhaust tone.

Matt

 

Matt, it is the muffler that will give you the biggest change in exhaust note, not the converter. A high flow cat is fine (may change the exhaust note only just slightly), but the critical parts are that it must be 3-way and it must be 50 state legal so as not to throw codes again.

I have not been shopping for any lately but I am sure you can find some direct fit made for your application:
http://www.autopartswarehouse.com/ap...01&modelid=681

This magnaflow 43000 series is also EPA and CARB legal (43005 should fit yours):
http://www.bestautopartsonline.com/4...converters.htm

The Cali spec vehicles are tough because of this issue:
"The California Air Recourses Board (C.A.R.B.) does not allow the installation of new aftermarket catalytic converters on OBD II equipped vehicles (1996 and newer models) unless the converter has been specifically designed and tested for OBD II applications. All new aftermarket catalytic converters that are legal for sale in California are identified as "OBD II Compliant". For a list of approved OBD II compliant aftermarket catalytic converters - please visit the C.A.R.B. web site at www.arb.ca.gov"

 

so getting a new cat means you have to have old one cut of and have a new one welded in ?

 

Elton,
Yes.....Unless you go to the dealer and have them install a bolt on replacement (flanges, pipe, cat, and all) or install an aftermarket bolt on replacement, however a lot of the aftermarket bolt on converters are not constructed nearly as well as what's on your truck now. Case in point...the Eastern converter that I just ordered and sent back. Not only would I have not put it on my truck after looking at it (it appeared to be very poorly constructed), but the rear O2 sensor port was totally incorrect. I sent it back and they received it last Friday and told me that it would be 4-6 weeks before the refund is credited to my credit card. Needless to say...I'm pretty pissed.

I'm screwed though because I do not think it's possible to cut out and weld in a replacement cat for the front one. The rear one yes, but not the front. I'm one of the few fourtunate ones to have somehow ended up with a dual cat system, and I couldn't be much further from California (I live in Alabama).

Matt

 

These CA spec'd trucks are just a nightmare to work on the emissions stuff. :pat:
Sorry you have to go through all this Matt.

 

Tell me about it....What a royal PITA!!!!

Matt

 

Matt,
I too have a Cali-equipped 4Runner, and if you recall it came from Alabama as well.
Is it possible that all 01'-up 4runners are Cali-spec?

 

my P0420 is gone, as is the smell out the rear of the truck

the exhaust, looks, sounds and performs great

Once removed I checked out the old cat, it wreaked, it also looked to be fairly well filled up, it was not broken up inside but you could barely see through out, whereas when I bought it originally and the replacement which is the identical model, you can see clearly through the honeycombed structure inside,,,,to the other end

My P0420 was coming on regularly as in every day, or every other day....I recently had a P0441 which has come on again a couple times,,,so I must have another problem.....however the P0420 low threshold yadda yadda yadda does appear to be gone..

I do think my cat was restricting performance, did seem to be clogged up quite a bit and there definitely is a little more oomph at the throttle, which I am not crediting entirely on the flowmaster muffler....vs the dynomax that was in there,,,I do think clogged cat was an issue