I've got a 00 4runner, 5speed, 101k miles, cali emissions, and the p0420 light has been on for a while.

im not too keen on spending the $2k+ for a factory dual cat assy, but I've read that any other cat(s) dont run "clean" enough for the computer to turn off the light. I dont want to miss an important check engine light because im writing it off to the p0420.

I do know about the urd piece, but it seems like a band-aid to me.

so, what I'm really wondering is, has anybody found an aftermarked cat that will still work with the cali emissions and not kick the light anymore?

actual experience would be helpful, as I dont want to buy and have installed random cats from my local parts supplier, still have the CEL and waste my money.

thanks for any input.

ETA: its a 3.4

 

Well I can tell you the Carsound universal cat doesn't work, I was throwing a P0420 every other day. Maybe if you put on 2 or 3 of them it would work.

 

if u have the 2.7L check manifold thats what mine was

 

You can try replacing your last 02 sensor. Replace the gaskets check for exhuast leaks and stuff. I realized that my 00 4runner i had a leak on my first cat on top. Because i ran my hand around it and i felt air coming out and i got it welded up to patch it up. This is sure cheaper than replacing the cat. While your at it replace all the exhuast flange gaskets and for heat/stress cracks on the flanges good luck.

 

anyone else?

theres gotta be somebody who has found a viable replacement for the factory cat that doesnt cost $2k+

 

I have 2.7l 4cyl 2000 taco. I live in Nj, I went to an Lc header and a Free flow cat from Lc. I only have the 1 cat from them and I throw no codes and just passed emissions . I do live in Nj but have a California Model Taco , I used a test pipe after the cat and put my 2nd O2 sensor in the test pipe and it works perfectly. I was getting an O2 code in the second location replaced the O2 and the cats with 1 cat and have had no problems so far.

 

Fink and I have been battling the same problem and we've not found a cheaper replacement.

He went with the O2 simulator, and I just keep turning off the CEL.

Erich

 

You could try an O2 simulator, works for me, I haven't had a P0420 since I put it on. http://www.urdusa.com/product_info.p..._id=1230100014

I've got a dual cat assy from a 2001 3.4 Taco with 27,xxx miles I'll sell for $280 plus shipping. I don't know if they will bolt up to a 4runner, but I'm sure a muffler shop could weld it in.

 

you can try the O2 mechanical type simulator. check on ebay under O2 simulator. that may fix the p0420 code.

its like 10bucks shipped.

very simple to install. just warm up your car and untighten the secondary sensor and attach the simulator w/ your 02 sensor.

ive never try the simulator but it works for some ppl

 

"This device may not be legal for use on pollution-controlled vehicles operated on public roads and is intended for off-road use only."

Those simulators would work good....for people who A. dont care about the environment B. Offroad app only C. Dont need to get emissions checks done.

It will fool the ECU, but it wont fool the emission station. You can find recerted factory cats around for about 1/4 the cost of new, and prolly cheaper. I know we have them here, but everything we have is Federal emissions.

 

OK, why won't it fool the station? In NJ, and I think in most places, they just jack into the ECU and check for stored codes. No tailpipe check for post 1996 cars at all. So if the ECU is happy, why would NJ Inspection not be happy?

Now that there is probably a stiff fine for doing it--that I believe!

 

They don't check anything in Oklahoma, nada, zip, zero. Right now anyway, there's some talk that may change in a few years.

 

well each state is different. here in WA they check tailpipes for any years. Most of the state has to get emissions. Luckily i do not.

 

here in TX, tail pipe check for only pre-obdII vehicles, others are being scanned through OBDII port.

 

NM is odd, They don't do emmisions for rural areas, but here in the ABQ metro it's tail pipe check for 1975-the OBDII changeover, after that, they just plug you into the machine and send you on your way if everything checks out. Pre 1975 is exempt.. bummer.

Andy

 

I have to disagree about not caring about our air. I could have easily decided to not do a double cat set-up on my 3.4 conversion, since I have no inspection, where I live.

I did install 2 Magnaflow cats on my truck for a couple of reasons. 1 - I do care enough about our air to do it, and 2 - the system was designed to run with 2 cats on it.

I do throw a very occasional cat code on my truck, now. I have not figured out why, precisely, nor have I determined a particular pattern to it. If I continue to get these nuisance codes, I will certainly think about putting that URD simulator on it, so that I won't mask other engine codes.

 

I would think that so long as your truck was running just fine before the cat died, then the O2 sim would work and pass emissions. You have to figure that other brand cats do the same things as the Toyota cats, but Toyota's ecu is too finiky. I ran O2 sims on my 99 Cobra that had Hooker Long Tubes and an off-road X pipe, no cats. I think it ran perfectly clean.

California emissions are controled by environmentalists that simply do not have any empirical data to support their political agenda. I care about the environment, but it is getting silly. Just another way to generate more revenue and satisfy the egos of congresspeople who have no other significant impact.

 

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amen to that. I'm in oregon and our jackass govrnor just enacted legislation for us to have california style emissions on our cars just to kiss the tree huggers butts. we don't have smog anywhere in this state but now we will have cars that run like crap.

 

You know what galls me too? The fact that if there were less smog requirements, fuel economy would go up. This is what manufacturers have to deal with. And the consumers too. Ever wonder why fuel mileage has gone down on some classes of vehicles? VW is one that has gotten hammered by this phenomenon.

 

FWIW, I'm running Downey headers, a single Magnaflow 3" cat and 3" piping through a Dynomax muffler on my 2001 Tacoma (originally dual cat equipped) swapped into my 88 4Runner.. and I've never thrown a p0420.. I was concerned about it but I haven't had any issues with it in the 4 years and 25000 miles I've been running it.