The shop doing the inspection will see all pending and/or cleared codes along when exactly they were cleared.

Really the only solution is to fix the problem, manually clear the code & drive through the relearn cycle. If all is good, the fault history will be "truly" cleared & you'll pass.

 

hi, I want to get it fixed before I take it for inspection. They are gonna do the same thing I am doing, and tell me to drive the car till the tests are done.

Let say the problem is with the purge valve and I replaced it with OEM one. Will the pending codes P0440 P0441 and P0446 clear the next time the test is run. Or do I need to erase them and restart all the EVAP tests again (the oxygen sensor, the catalytic test, etc).

 

So you're doing the repairs yourself? By the way you phrased it, kinda hard to tell.
If that's the case, once you replace the parts, clear the codes & drive around until the test shows all modules are present (aka "ready for test" on some scanners).
Waiting for the codes to correct themselves can take some time & can be unpredictable, usually much quicker to just clear & drive until the aforementioned readiness state is reached.

 

Short answer is yes they will clear themselves, eventually. If the problem doesn't come back within a set number of drive cycles the computer will clear the pending code.

BTW I had the same 440 and 441 come up on my Camry. Funny how our cars are almost 10 years apart and those purge valves are still problematic. Good thing they're an easy, cheap fix. Seems to be a Toyota thing.

 

Pending codes will clear itself. It isn’t necessarily a fault unless it posts a cel. A pending code is set when the fault is just above or below a limit set point or out of range.

Evap has a set amount of time per cycle. If at any point during the self check, it will post a cel. Some members have said their repairs have been a failed evap purge solenoid under the hood.

A smoke check is required to find the leak. Gas cap is the first place to start.

 

I did the same fix on my Camry, purge valve and gas cap. Parts from the dealer for about $115 and 5 minutes of my time. Love the simplicity of 4 cylinder Toyotas. I cleared the codes but one immediately came back as a pending code. CEL never came on again so I never bothered to see if it was still there.

 

Once an evap repair has been done, you have to drive a specific evap drive cycle in order for the computer to run the evap tests on the system. If you don't drive the specific drive cycle, you can literally drive for thousands of miles and it won't run/complete the test. That exact thing happened to me until I drove in a very specific manner, then it was pretty quick to complete the test and remove the pending codes. I no longer remember how I did it, but I'll see if I can find it and report back here.

I didn't have any problems using a new Beck/Arnley purge valve. Much cheaper than the OE part. B/A is a decent brand (usually). Also, for the VSV on the charcoal canister, I used the Aisin brand (same as the OE Toyota part) but much cheaper.

 

Thank you all for the tips and experiences. I am going to wait for the OEM parts to arrive next week, install them and see if the pending codes P0440 P0441 and P0446 clear without erasing them.

My son might have to drive from NYC to Boston before end of the year. if the pending codes clear before his trip, then all good. Otherwise I will erase all the codes before his trip and see. I will update you all later on the outcome.

Happy holidays to all.

 

Follow up post. Learnt something new.
Installed the OEM gas cap and purge valve. Went to the gas station and filled up the tank, two blocks from the gas station, the check engine light came on. It has to be the new gas cap. I re-tighten it, and at that point, I decided to reset the check engine light with the OBD scanner. In hindsight. I should have left it alone and see if the check engine light would go away.

A strange thing happened when I looked at the MIL status this time with the OBD, the pending P0440 P0441 and P0446 codes were still there and the evaporative test, etc were passed. It's strange, because the day prior, I already erased the pending codes with the OBD scanner, so the evaporative test should be Incomplete with no pending codes.

All i can think of, is that maybe when I erased it with the OBD the day prior, I turn off the car, and the changes did not stick. Hmmm

This time, i erased it with the OBD and turn off/on the car. This time the reset stuck.

I drove it around couple of times, the evaporative test which take the longest, passed. with no pending codes. Got the new NY inspection sticker. Yea!

One lesson learnt is to always buy OEM evaporative valve, or any other parts important parts. My non-dealer mechanic replaced the purge valve way back, and I didn't even remember he did. He probably did it when I first brought the car in because of these same codes. Thinking back, I ended up replacing the catalytic converter with an aftermarket one (he did a custom welding job), that perhaps was not even necessary. Hard lesson learnt.

The irony is that this car is going to Ohio, where my son is starting his new job. And in that county, they don't require emission testing at all. All is needed is a VIN and Mileage check at a designated location.

Thank you all for your help and insights.

To help somebody else, i got this from another forum, forgot where. This time, the evap test took less time around. It might not be for every car, but at least it provides some reference, as opposed to guessing.

Toyota catalytic converter drive cycle

The catalyst drive cycle from a Toyota bulletin;
Preconditions
The monitor will not run unless:
MIL is OFF.
ECT (Coolant Temp) is 176F (80C) or greater.
IAT (Intake Air) is 14F (–10C) or greater.*

For 2002 MY and later vehicles: The readiness test can be completed in cold ambient conditions
(less than 14F / –10C), if the drive pattern is repeated a second time after cycling the ignition OFF.

Drive Pattern Procedure
Connect the OBDII Scan tool to DLC3 to check monitor status and preconditions.
Note the IAT (Intake Air) value during engine startup. The driving time must be adjusted
during step “a” based upon IAT (Intake Air) value at startup.

a. Drive the vehicle at 40 – 55 mph (64 – 88 km/h) for the time described below:
—If IAT (Intake Air) was less than 50F (10C) when the engine was started,
drive for 7 minutes.
—If IAT (Intake Air) was greater than 50F (10C) when the engine was started,
drive for 3 minutes.

b. Drive the vehicle at 35 – 45 mph (56 – 72 km/h) for approximately 7 minutes.

NOTE:
Drive with smooth throttle operation.
Avoid sudden acceleration.
Avoid sudden deceleration as much as possible with the throttle fully closed.
If readiness status does not switch to “complete,” ensure preconditions are met, turn the
ignition OFF, then repeat steps “a” and “b.”

Note that the engine temperature must be above 176F. Your thermostat opens in the 176-183F range. If you have an old thermostat that doesn’t close tight you may not reach the minimum temperature for this monitor to start.

 

Thanks for reporting back, and I'm glad you have it fixed (this is confirmed with the evap monitor completing with no codes, pending or otherwise).

I'm not following you about the replacement of the gas cap, though. Do you mean when you installed the new OE gas cap, that you perhaps did not tighten it enough? You then checked it and retightened it? It should make a clicking noise when it's sufficiently tight. The fuel filler neck (at the exact location which makes contact with the rubber seal of the gas cap) should be smooth. By "smooth", I don't mean as smooth as glass, but if it is rough or has burrs, it will tear up the rubber seal of the gas cap in short order, resulting in a leak because the seal was compromised.

That drive cycle you posted is for the catalyst system, not the evap. Although there are some similarities, there are also some differences. You can inadvertently satisfy the test drive cycle while doing another one which may be slightly different. Normally, the evap drive cycle won't run or complete its evap test unless the fuel level is between 3/4 and 1/4 of a tank. There are one or two other requirements which I posted on my thread: How I Fixed P0441, P0442, and P0446.

If your old gas cap was faulty, that would explain one or two of your codes. A smoke test can confirm a leaking gas cap. P0441 was most likely the purge valve, as was in my case. It opens up when commanded to do so by the computer. The other codes were some evap hoses and possibly the charcoal canister. You can have these codes and a smoke test might still show no leaks.

 

Thanks for reporting back, and I'm glad you have it fixed (this is confirmed with the evap monitor completing with no codes, pending or otherwise).

I'm not following you about the replacement of the gas cap, though. Do you mean when you installed the new OE gas cap, that you perhaps did not tighten it enough? You then checked it and retightened it? It should make a clicking noise when it's sufficiently tight. The fuel filler neck (at the exact location which makes contact with the rubber seal of the gas cap) should be smooth. By "smooth", I don't mean as smooth as glass, but if it is rough or has burrs, it will tear up the rubber seal of the gas cap in short order, resulting in a leak because the seal was compromised.

That drive cycle you posted is for the catalyst system, not the evap. Although there are some similarities, there are also some differences. You can inadvertently satisfy the test drive cycle while doing another one which may be slightly different. Normally, the evap drive cycle won't run or complete its evap test unless the fuel level is between 3/4 and 1/4 of a tank. There are one or two other requirements which I posted on my thread: https://www.toyotanation.com/threads/how-i-fixed-p0441-p0442-and-p0446.1791383/unread

If your old gas cap was faulty, that would explain one or two of your codes. A smoke test can confirm a leaking gas cap. P0441 was most likely the purge valve, as was in my case. It opens up when commanded to do so by the computer. The other codes were some evap hoses and possibly the charcoal canister. You can have these codes and a smoke test might still show no leaks.

Hi John, I did tighten the new gas cap before i left the gas station. So i am not sure what happened. I run my finger through the rim and retighten it. No MIL light since.

And you are right, the routine is for the catalyst converter. My son is driving to Boston today. I'll let you know if those evap codes pop up again.

 

Evap codes are the most annoying to troubleshoot. Theres so many different components and hoses that can break in the life of any vehicle.

P0455 and 0456 are the most challenging. This is because it could be upstream or downstream. Some have had success with just replacing the vsv at the canister or the entire canister. Some have found the filler tube vent hose damaged.

Upstream is the purge solenoid and then the hoses coming from it to the canister. The ecu sequence for the evap check is another thing to keep in mind. If the system can’t hold pressure for a specified amount of time, the CEL will be turned on.

I’ve had a P0455 for the past 10 years. Theres a tsb issued on my Mazda 5. However, the fix doesn’t guarantee to work. Read many posts about the harness being replaced with no long term resolution.

So if your state emission check allows for any of the 7 monitors to be incomplete and no check engine light, then you’ll be fine. I can reset the CEL and then emission test. But I do it when it’s at operating temp and it stays off long enough for the test to pass.

 

---Update---
Hello all,
my son came back from his trip from NYC to Boston, no more P0440, P0441, P0446 codes, so the issue was the after market purged valve or the 20 year+ old gas cap. I am leaning toward the purge valve, because I tested the after market one with a manometer by blowing through one end normally (not hard), and there is a .3 psi registered reading.

But a code surfaced while in Boston. It's a P0171 - System Too Lean Bank 1, it's listed as both Confirmed and Pending. I looked it up, it's saying the there is too much air in the mix.

I will have my mech check it out on Monday. Meanwhile, i'll do some research today and see if that's something I can deal with myself.

 

---Update---
Hello all,
my son came back from his trip from NYC to Boston, no more P0440, P0441, P0446 codes, so the issue was the after market purged valve or the 20 year+ old gas cap. I am leaning toward the purge valve, because I tested the after market one with a manometer by blowing through one end normally (not hard), and there is a .3 psi registered reading.

But a code surfaced while in Boston. It's a P0171 - System Too Lean Bank 1, it's listed as both Confirmed and Pending. I looked it up, it's saying the there is too much air in the mix.

I will have my mech check it out on Monday. Meanwhile, i'll do some research today and see if that's something I can deal with myself.

At least you got 20 years out of it, I just did the same repair on my Camry and it was only 8 at the time. Anyway, at least it's a cheap fix and glad the old girl is still taking care of the family.

 

P0171 has a 90% chance of being the intake manifold gasket, especially when the weather is cold.

If the intake manifold gasket has never been replaced, it should be replaced now (first) before worrying about any other cause. Make sure to use the updated, orange colored OE Toyota gasket.

 

Check the simple things first. Is the air filter box sealed and fastened correctly? Check for cracks in the intake hose, 20 year old plastic cracks with age.

 

I think something is loose, i did take out the manifold tube and the air filter cover apart. I will re-inspect everything, clear the code and see if it comes back. I have never see P0171 til now.

And i just clean off the grimes off the manifold with a damp clean cloth — no throttle cleaning fluid needed. I'll let you know how it goes later.

 

I think something is loose, i did take out the manifold tube and the air filter cover apart. I will re-inspect everything, clear the code and see if it comes back. I have never see P0171 til now.

What year is your Gen 9 Corolla?

 

---update---
it's the first year car (2003 matrix), right after it launched. The interior compartments fit were loose, the small door would popped open while moving. lol

After i got my obligatory minivan, it has not been driven much then. It has around 89,000 miles.

Yesterday, i took the manifold hose apart again, clean the throttle, check the air filter top casing, the hoses, etc. Re-tightened everything.

Today, i went out for a short errand, Did the scan again, and the pending P0171 disappeared. Yes!!.
The stored P0171 code is still there — of course. So I erased it. It seems like something was loose when I re-assembled the manifold hose and the air filter housing. I am hoping this is it.

BTW, only the Puralator air filter would fit and close correctly — or rather easily. I had a new aftermarket one that i got from auto zone ages ago, and the housing would not close tight, there is 1/8 gap on the right clamp. hmmm. I ordered another Puralator air filter.

I will update if something else happens. Thank you all!

 

On this gen, there’s a way to close it completely. I’ve had this issue often after changing filters. The housing is a clam shell and none of the air filter should be seen or a gap.

You’ll take the housing and push it towards the throttle body. It’s like a clam shell and the tabs have to align just right. If there’s a gap on the back side, you’ll have to do it again. One time it took almost 6 times to get it right. It’s not something you deal with often, so I tend to forget how it’s done.

 

I actually did try it 4-5 times with the non Puralator air filter. I even tried it two-three times — as you suggested, by pushing toward the engine, checking the hinges, and making sure the casing was not clamping the seal on the filter. No dice. When i placed the old Puralator filter back, it closes completely, with no gap. So I gave up and put the old one back in for now. lol.

I figured why mess with the "other" brand, when the known brand works. Beside, I was also trying to eliminate one more variable that could have caused the P0171, however minute that could be.

btw, I did the same manometer blow test with the new oem purge valve, and the registered leak reading was .003 vs the .3 I was getting with the after market one. So the problem was definitely the after market Dorman purge valve. In my case, it lasted for 2 years or so.

This also validate that gas cap can last over 20 years, so the chance of that going bad is pretty slim, unless there are physical damages. Cheers.

 

I know this is an old thread, but i want to keep the history together and provide an update since I last posted. As i said before, my son took the car to Ohio in February, in a county that does not have emission inspection. He had to re-register the car under his name, buy his own insurance, new plates and title, etc.

Before he left in February, I changed the spark plugs, and the engine cover gasket myself (OEM parts), I didn't change the spark plug coils, I will tell him to do it himself.

In case you feel inclined to do it yourself:
Engine cover gasket torque values
outer 96 in-lb (10.8 > 11 Nm or 8 ft-lb)
inner 80 in-lb (9.04 Nm or 6.6 ft-lb)

Spark plugs torque values
The spec value of torque in the Toyota shop manual is 18 ft-lb (216 in-lb, 25 N-m)
Torque Specs Cast Iron: 26-30 lb. ft. Aluminum: 15-22 lb. ft. (from Denso site)

Before he left, there was a small leak in the radiator plastic head (the small piece all the way to the left), it was an after market radiator that was installed like 2 years ago, I had to replace it again with another aftermarket because there was no time to wait for the shipping of an OEM one. If you have time, get the OEM one, even if you have the auto shop do it for you.

He was flying back to NYC 2 weeks ago and midway to the airport in Columbus, the engine stuttered above 70 mph, and eventually the dashboard light went dark, even though the gas pedal was still accelerating. He chose to stop, as he should, and the car would not start again. Ohio highway patrol happened by, and the car was towed, and he caught an uber to the airport. The tow(s) was over 800 dollars, first tow was to tow it to the tow company (they said they have their own shop and could "fix" it), and another to tow it from the tow company to the auto repair shop (they had it for 5 days and couldn't get to it, blah, blah). Guys, get AAA, with their plus plan, they will tow it to a shop of your choice within 100 miles. My son has the roadside assistance from Liberty Mutual, but the wait time for their tow was 3 hours — per the app.

It turn out the problem was with the alternator and a blown 100 amp fuse. The new auto repair shop fixed it at a cost of about 550, plus they changed the transmission oil (22 years old) and recharged the battery, so the total was about 700 dollars. It's a AAA shop, so there was a 10% discount on labor (I got him the AAA plan afterward).

Before the issue with the alternator, there were only minor issues. The hood latch was rusted and would not open, he bought the part and replaced it himself — so proud. And the intermittent speed sensor warning light pops up and goes away on the dashboard, it has been like this for last couple of years. I think it's a loose ABS sensor in the wheels. The transmission does not have a speed sensor, because I bought this car with ABS as an option. My mechanic couldn't find a sensor on the back of the engine block. And I spoke to an AAA recommended shop in Ohio, and they also said that without a code in the ODB2, they can't look into it.

Even with $1,500, it's still better than buying a new car. Beside, Liberty Mutual should reimburse about 400 of the 800+ tows, as stipulated in their roadside assistance coverage. We'll see.

Cheers