P0420 light needs your advice!

[maxximr]

hey guys I'm max and currently new here.

I have a few questions, so I bought myself a 2004 Tacoma Crew Cab Trd Prerunner (lovin it!) and need to smog it (California style), but one problem: my CEL is on, code is P0420
http://img.tapatalk.com/6b27fc47-8075-f482.jpg
there it is.
The smog guy pointed at this
http://img.tapatalk.com/6b27fc47-80af-b1c9.jpg
the catalytic converter,
he says it's not original and may be causing my problem.

my questions are:
should I buy new spark plugs and o2 sensors first (or just the bank 1 o2 sensor) and try that? The truck has 73000 miles on it.
I've also been reading it could be something with the gas cap? mine seems fine but I do have trouble filling up, I have to hold the nozzle up or it shuts off and won't pour. is that an issue of concern?

If it is that converter, where can I get one for a good price (I'm on that college student budget)? or can I just get a new exhaust system that will work with CA emission laws and has all those fancy converters?

thanks in advance!

[4x4mike]

Did the smog guy run the reader and give you the code? Looks like a phone screen shot. That cat is not factory and most likey a cheap easy fix for the PO. You can find another cheap easy fix but it won't last long. Spark plugs might be a waste of money.

Welcome to UY.

[Robinhood4x4]

Do you have any dash lights?

[Obi..]

^That. If the CEL is up you know it's a trapped vs. temp code. That said three things...

Welcome to UY! :D

Put a factory CAT in there, especially for CARB, it may pass visual but it will never pass sniffer. Heck I'd be surprised if it passes visual with those neck-downs on there. Make sure when you get insurance for it you go with Comprehensive, specifically ask if small things like converter theft are covered, I just had another one stolen recently and put on a temp one but come smog I have to go O/E.

Let's see a pic of this Tacoma! ;)

[maxximr]

the only unusual dash light on is the CEL (the code is pending in the screenshot because I recently cleared it and it takes time to light up again). I'll post pics soon, thanks guys!

[Robinhood4x4]

Then I'm going to say it's not the gas cap because that throws the traction control lights for some reason.

[maxximr]

Then I'm going to say it's not the gas cap because that throws the traction control lights for some reason.
very good to know, thanks!

[Good Times]

welcome to UY!

Not sure if you've already worked on this issue but if it's still an issue try this.

Clean your MAF sensor which is located right by your air filter. At one point I had a p0420 error pop up and cleaning the MAf sensor fixed my CEL.

Give that try first (it's the cheapest option instead of replacing all of the O2 sensors).

Good luck!

[fenrisx]

Not saying this is the case, nor have I experienced it first hand, but I've read that people have a lot of issues with after market cat's throwing codes. Might be worth looking into if cleaning the MAF doesn't work.

[maxximr]

I welded on a new cat today that I bought from Pep Boys Auto Parts for $200. Ran it through and after 50 miles the light came back on. What do you know P0420 is back...anytime I clear it, 50 miles later it's back...I just don't get it...

[YotaFun]

Thats about the mileage it takes for all the monitors in a Toyota to reset.
Aftermarket cats really don't do the trick for Toyotas.

If yours is a Cali Emissions truck you have two cats, if your throwing a P420 code, its most likely going to be the front cat that failed, I can't remember if the 04 Tacos are Sensor, Cat, Sensor, Cat, or like my stepdads 02 Runner, Sensor, Cat, Cat, Sensor.

If its Sensor, cat, sensor, cat, you need to replace the front cat.

If its sensor, cat, cat, sensor, you need to replace both cats.

Just from my experience and time in the shop this is how it usually works out, again your going to want to go Toyota on these, I know it sucks to hear, but honestly its only what I have come across, some have been lucky with the aftermarket bolt ins but its rare...

[maxximr]

sensor cat cat sensor. my theory is that when the cat was stolen and torched off, the torch may have ruined the back sensor becuase the cut was really close to it. so im gonna change that sensor next, and if that fails... well I hope it doesnt.

[Robinhood4x4]

That sounds like a good plan.

A guy at work got his cat stolen and his aftermarket cat worked for a few years and then he had to replace it again.

[maxximr]

Thanks everybody for the good advice! Yes the sensor worked, aftermarket cat was an unnecessary waste of $200, oh well.. aftermarket sensor did the trick, should pass smog now! hopefully I get it painted soon and could post some pictures

[DHC6twinotter]

Awesome, glad you got it working. Welcome to the forum.

[Robinhood4x4]

The sensor might not have been the original problem though. It's conceivable that the aftermarket cat was bad and the sensor was still good, but the sensor got damaged after you welded on the new cat.

Anyway, glad to see you got it fixed.

[maxximr]

idk... I took it off to weld it...but i did just scan it, and the catalyst system check is still incomplete after 120 miles :/ maybe im just getting my hopes up too soon

[YotaFun]

Usual Toyota Monitor set status you have to drive the vehicle between 50-55 mph for a few miles or so and it will set, Tacos and 4Runners are usually 10, be glad its not a sienna, you would be making a cross country trip to try to get those monitors to set

[maxximr]

Usual Toyota Monitor set status you have to drive the vehicle between 50-55 mph for a few miles or so and it will set, Tacos and 4Runners are usually 10, be glad its not a sienna, you would be making a cross country trip to try to get those monitors to set

50-55 huh, didnt know that, define "few miles" though I need that catalyst system to complete and the evap system

[YotaFun]

I drive my 4Runner 70 miles a day, usually I can get every monitor but the evap to set by the time I get home (just after clearing the codes at work).

Evap will then usually run overnight, depending on where your fuel level sits.

[maxximr]

I drive my 4Runner 70 miles a day, usually I can get every monitor but the evap to set by the time I get home (just after clearing the codes at work).

Evap will then usually run overnight, depending on where your fuel level sits.
thanks, idk much about how the evap system works, so idk..

[maxximr]

doing some research I found out to complete the evap system test, I have to drive according to an LA#4 drive cycle, which is pretty much a traffic drive of 20 minutes

[maxximr]

PASSED SMOG! :D I learned a few things: according to CA Emission standards you only need 4/7 system checks complete. Just gotta visit the smog guy that knows better than to send you on random drives which won't do jack unless your driving a certain way like LA4 drive cycle or another kind..wasted gas, money, and time when all of that could have been avoided...

but thank you guys for leading me into the light!

[Seanz0rz]

congrats!

[4x4mike]

PASSED SMOG! :D I learned a few things: according to CA Emission standards you only need 4/7 system checks complete. Just gotta visit the smog guy that knows better than to send you on random drives which won't do jack unless your driving a certain way like LA4 drive cycle or another kind..wasted gas, money, and time when all of that could have been avoided...

but thank you guys for leading me into the light!


Were did you end up going for the test?

[maxximr]

PASSED SMOG! :D I learned a few things: according to CA Emission standards you only need 4/7 system checks complete. Just gotta visit the smog guy that knows better than to send you on random drives which won't do jack unless your driving a certain way like LA4 drive cycle or another kind..wasted gas, money, and time when all of that could have been avoided...

but thank you guys for leading me into the light!


Were did you end up going for the test?

the first time off of auburn and pasadena, then finally elkhorn blvd and 32nd theres a little smog shop in the warehouses by dalat autobody parts

[jrallan26]

I miss the California weather.... Don't miss the smog checks and traffic.....