PO446 and PO135

[soccerfan]

I have a '99 bone stock as my daily driver, with 119K on the clock.

Car has been throwing both codes for a while. Finally sourced a replacement charcoal cannister from a boneyard and replaced this past weekend. Was not too difficult, but did have to drop the exhaust 3-4 inches to get it out the passenger side.

Cleared codes and patted myself on the back (prematurely).

Codes are back. Is it usual to get these two codes in tandem?
Any ideas for the next step ?

I have read all available posts on the two codes in the G1.5 forum.

Thanks in advance for your help.

[Chinky420]

P0135 - Heated Oxygen Sensor Heater Circuit Malfunction (bank 1, sensor 1)
· Open or short in heated oxygen sensor heater circuit
· Heated Oxygen sensor heater malfunction
· PCM malfunction

P0446 – EVAP System - vent control malfunction
· Same as P0441

P0441 – EVAP Control System - incorrect purge flow
· Open or short in VSV circuit for EVAP
· VSV for EVAP
· Open or short in vapor pressure sensor circuit
· Vapor pressure sensor malfunction
· Open or short in VSV circuit for vapor pressure sensor
· Malfunction in VSV for vapor pressure circuit
· Vacuum hose blocked, damaged, or disconnected
· Charcoal canister malfunction




P0135 is the oxygen sensor, bank1 sensor1 (between engine and firewall, not between engine and radiator). buy new O2 sensor (if federal spec, i think it's an A/F meter if it's cali spec). i believe that there is a DIY tutorial in the gen 1 tutorial section. i've had this CEL on my lara for about a year now, if you don't replace, you're gonna be running rich (safety mode), but your engine shouldn't blow up because of the bad O2 sensor.

and i don't know jack about the evap system, so someone else will have to help you with that.

[soccerfan]

UPDATE.

now have 124K. Ordered Bosch O2 sensor via internet and installed this last weekend. Cleared codes and waited.

Yesterday PO446 came back, PO135 appears to be gone.

Replacing the O2 sensor was actually easier than I had built it up to be.
Rented O2 specific sockets from Autozone ($25 charge for tool when you check out, full refund when you return it). Had to go underneath to unplug the wires (only so I could see it....tried just feeling it, but no success there).
Standing on the drivers side of the vehicle, reached in with right arm and put socket in correct place, little pressure on the ratchet and it broke free.
Did not use PB Blaster or anything else. Installation is the reverse, and was able to feel the wires connection back into place.

Now, on to the PO446. I have replaced the cannister with one from a boneyard, and still have the code. What are the other likely culprits?
I tried to follow the vacumn hoses to the front, but did not have the car raised and that proved fruitless. What is the likelyhood that I replaced a bad cannister with a bad cannister? Is there a sensor that needs to be replaced ?

My inspection sticker ran out Feb 2008 so I've been driving around for 13 months now with an expired sticker.......

As an aside, even with the vehicle throwing two codes, I recently went on a 700 mile weekend trip and averaged 28 mpg.

Thoughts ???????? suggestions ???????

[Midias]

My p0446 was the valve on top of the canister.

[Solorange]

Ive gotten PO466 before. I thought it was the valve on the canister as well. It ended up being the gas cap seal. Check that.

[aleki2424]

Toyota came up with a newer valve following the tsbs on the issue, since this is fairly common.I tried all the above (gas cap etc), didnt work, including replacing the vacuum switching valve (part no90910-12199) I think, which didn't work either
Stealerships will recommend getting a new canister, but to me, paying $800 is a lot of $$.

[ASG14]

You should never use Bosch O2 sensors on a Toyota. They tend to have a very high failure rate for some reason. Same with the spark plugs.

[99sle]

Toyota came up with a newer valve following the tsbs on the issue, since this is fairly common.I tried all the above (gas cap etc), didnt work, including replacing the vacuum switching valve (part no90910-12199) I think, which didn't work either
Stealerships will recommend getting a new canister, but to me, paying $800 is a lot of $$.

"My p0446 was the valve on top of the canister."

Ive got both codes also. For the po135 code, a new denso universal o/2 sensor from autozone was cheapest so far at about $60. With the po446 how much is the cannister at the boneyard? Is there an aftermarket avail. and how do you get rid of the 446 code? $800 is silly. I think Im going to try and get both at the boneyard. Can you get the valve for the cannister seperate brand new?

[soccerfan]

My replacement canister came from a buddy who manages a boneyard.
It was the best price possible.

The O2 sensor replacement took away the 135 code, but I still have the
446. Someone mentioned replacing the VSV to clear this code. I have yet to price that at the stealer. Still getting 28-29 mpg on road trips so the fact that my inspection is a year out of date is the only issue. Will have to address this at some point, but not a huge pressing issue.

Welcome any definitive answers on solving the 446 !

[99sle]

The tech at the toyota dealership told me that the 446 code usually means there is something wrong with the vaccuum hose that runs from the canister to the top of the air cleaner assy near where it ends at the throttle body. For the gas cap to be bad you generally will have 3 codes 446,441 and 440(I think).
For the 135 code, I ended up getting a denso o2 sensor from carquest(its in a carquest box with denso written on it) non universal for $90.

[99sle]

The small 4 inch long hose on top of the motor leading into a little barrel was the culprit here. It was all brittle and dryrotted a big slit down the backside of it. It has a clamp on each end that you can squeeze to remove.

[ozone]

You know there is a procedure for this kind of thing. It sounds like a lot of people are just going by what some mechanic or parts guy at the dealership says. I followed the repair manual and found my P0446 problem. You can find a subset of that on my site, here: http://www.ozone1000.com/blue_frame_solara.htm

If you want the original genuine Toyota part, I will be happy to sell you one for $500.00. I can sell these at this all time low price because the one at my dealership was only like $270.00. I don't know where the $800.00 price came from, but just because one guy got that price at the dealership doesn't mean you shouldn't call your dealership to check. It also came with all the VSV's attached to it as a whole assembly. In my case, it was the actual charcoal cannister, that wouldn't hold vacuum.

I'm sure different people will have different problems causing this, but please get your hands on a procedure, that way you know you have solved the exact problem. After I did this repair, the gas mileage went up from about 26 or so to 29 on the highway.

If the portions of the procedure on my site aren't complete enough, send me a PM and I'll see if I can't get you the whole thing.

Good luck.

[soccerfan]

Update.

Last weekend I actually spent the time to follow all the vacuum lines around and - shocker - I found that a line going into the airbox was not attached. Attached it and cleared codes.

Now, have a different code, PO402 which has to do with EGR. I tried to clean the EGR the same day, but that appears to be a dead end. Still throwing 402, so at least I have it narrowed down to a single code again.

Is it possible for one code to hide behind another ? By finding the solution to the 446 have I gotten one step closer to the actual problem or is this a shell game ?

Fun fun fun.

[soccerfan]

Current Update.

After finding the unplugged vacuum hose and "cleaning" the EGR now I've migrated to two codes that are related.

I removed the EGR and the tube from the vehicle and gave them an hours worth of attention trying to resolve. Carb cleaner and pipe cleaners, etc.
Reinstalled and cleared codes.

Now I'm getting P0402 and P1411. I've cleared and let them come back three times now. First to appear is 402, then about 60 miles later 1411 comes back. I've looked at the explanation, one of them indicates "excess flow" other references "position sensor" or somesuch.

I'm trolling ebay for an EGR, and have priced them at the local autozone. Probably will call the stealer too, just for shock value. I hope that I'm getting closer to a resolution. Still getting 28/29 mpg on long road trips, even with the codes.

Hope my ramblings on the subject are helpful to another.

[soccerfan]

UPDATE. Finally received a ticket for having an expired inspection sticker. Officer from my town did not like my answer when he asked why my sticker was so far out of date.

Took vehicle to a shop newly opened who came highly praised by close friend. Former dealership tech now out on his own. After listening to the whole saga he asked me to leave the vehicle with him for a bit. Couple hours later he calls and says there is a TSB that recommends replacing some valve on the canister that will clear the "false code". $215 parts and labor, so I had him do that, inspect it for the new sticker and replace a headlamp that was out. The next day after I picked the vehicle up (with the shiny new inspection sticker on it) the code is back. I cleared it using my scangauge and it came back - again - the next day. I called him, he indicates there is a hose on top of the gas tank that probably needs replacing, but his recommendation is to replace the canister with a new one from the stealer. He indicates that this is a false code and the issue is specific to the 1999's. what luck.

My immediate problem (lack of current inspection sticker) is solved, so I'm going to wait until my wallet recovers from the last beating before trying to resolve this.