Obdii Reading Of P0440 And P0446

[Germex]

I have a 2000 RX 300 and the Check engine light came on. I went to Autozone and they hooked up thier OBD II meter and codes P0440 and P0446 came up. I recently read on the website that these readings (P0440 and P0446) have to do with the Evap System. The issue can come from a disconnected hose on top of the air box and or possibly the gas cap not being tightened enough. Well I checked to see if any of the hoses were disconnnected and did not find any. I also checked and the gas cap appeared to be tight but removed it and made sure it was. I then removed the EFI fuse to reset it but the check engine light is still on.

Any suggestions.

Germex

[dgorrie]

I don't recall the code that my '99 RX300 had, but over the years I've had it, I've replaced two gas caps. In both cases, they "seemed" tight, but apparently weren't airproof. Replacing the gas cap with a generic from Autozone, then driving it a couple of days, and the MIL light cleared up. For the low cost, I'd try that first, then chase the issue if the light stays on. Just my thought.

[RonsRX300]

Double check the hose that comes off the airbox. It can appear to be connected to the airbox, but is really disconnected from the tube that runs to the rear of the vehicle.

[Germex]

I don't recall the code that my '99 RX300 had, but over the years I've had it, I've replaced two gas caps. In both cases, they "seemed" tight, but apparently weren't airproof. Replacing the gas cap with a generic from Autozone, then driving it a couple of days, and the MIL light cleared up. For the low cost, I'd try that first, then chase the issue if the light stays on. Just my thought.

Okay, thanks I will give it a try and see what happens.

[Germex]

Double check the hose that comes off the airbox. It can appear to be connected to the airbox, but is really disconnected from the tube that runs to the rear of the vehicle.

Okay I will check it later tonight again to see if that could possibly be it. THanks

[Ghostdiver]

Double check the hose that comes off the airbox. It can appear to be connected to the airbox, but is really disconnected from the tube that runs to the rear of the vehicle.

Okay I will check it later tonight again to see if that could possibly be it. THanks

I know that bringing up a month old post is not the best thing to do, but I cannot email or PM the OP since I am a newbie (i guess). Anyway, I am curious to find out the what the end solution to this problem was if it was fixed or not.

Having the same problem; except I have three reoccurring codes; (P0440, 441, 446). Tried to search for a common issue and the only one I have found was the air hose to the air cleaner. Was curious if this was the problem or if something else was the culprit.

[Paticake]

I had the same three codes, and it WAS the hose off the air filter box. Start there first.

[Germex]

Double check the hose that comes off the airbox. It can appear to be connected to the airbox, but is really disconnected from the tube that runs to the rear of the vehicle.

Okay I will check it later tonight again to see if that could possibly be it. THanks

I know that bringing up a month old post is not the best thing to do, but I cannot email or PM the OP since I am a newbie (i guess). Anyway, I am curious to find out the what the end solution to this problem was if it was fixed or not.

Having the same problem; except I have three reoccurring codes; (P0440, 441, 446). Tried to search for a common issue and the only one I have found was the air hose to the air cleaner. Was curious if this was the problem or if something else was the culprit.

Sorry for the late reply but don't always check. I put a new gas cap on and the problem went away. I filled the tank with gas and it appeared to be fine for about a week. Well got a call this moring from my daughter saying the check engine light came back on. I am pretty sure that if I check the with the OBD meter Iwill get the two codes P0440 and P0446 again. As I said earlier I checked the hose that comes off the air box and it is attached. I am starting to get a little frustrated. Any other things I can try??

Thanks for all the support so far.

Germex

[Paticake]

Did you clear the codes? I disconnected the neg battery cable for 5-10 minutes and that worked like a charm.

Check the hose again, make sure it's clipped on.

[Germex]

Did you clear the codes? I disconnected the neg battery cable for 5-10 minutes and that worked like a charm.

Check the hose again, make sure it's clipped on.

Yes I had the person at Auto Zone clear the codes and I put a new gas cap on. After they cleared the codes and I put a new gas cap on it was fine. I used the car for about 2 weeks and then filled the tank with gas about 1 week ago and now the vehicle is at about a half of tank of gas and the light came on again. I just went out and checked the hose again. I even took the top off the air box to verify the hose was connected. As far as I can tell the hose is connected. Will it help to disconnect the negative battery cable? Do you know will that clear the codes and turn the check engine light off?

Thanks,

Germex

[Germex]

Did you clear the codes? I disconnected the neg battery cable for 5-10 minutes and that worked like a charm.

Check the hose again, make sure it's clipped on.

Yes I had the person at Auto Zone clear the codes and I put a new gas cap on. After they cleared the codes and I put a new gas cap on it was fine. I used the car for about 2 weeks and then filled the tank with gas about 1 week ago and now the vehicle is at about a half of tank of gas and the light came on again. I just went out and checked the hose again. I even took the top off the air box to verify the hose was connected. As far as I can tell the hose is connected. Will it help to disconnect the negative battery cable? Do you know will that clear the codes and turn the check engine light off?

Thanks,

Germex)

Ok in follow up to my above message, I went to Auto Zone again and had the same OBD reading (P0440 and P0446). Checked the hose off the airbox and it is attached. Put a new gas cap on. Reset the the check engine light and it was fine for a few days. Filled the car with gas yesterday and light came on again later that day.

Not sure what else to check? Does anyone have experience with these two code readings. Could it be a bad tube or seal, bad vacuum hose, something in the charcoal canister, Vapor pressure sensor??? Just looking for some input on what to check next.

Any help would be greatly appriciated.

Thanks,

Germex

[RonsRX300]

Did you clear the codes? I disconnected the neg battery cable for 5-10 minutes and that worked like a charm.

Check the hose again, make sure it's clipped on.

Yes I had the person at Auto Zone clear the codes and I put a new gas cap on. After they cleared the codes and I put a new gas cap on it was fine. I used the car for about 2 weeks and then filled the tank with gas about 1 week ago and now the vehicle is at about a half of tank of gas and the light came on again. I just went out and checked the hose again. I even took the top off the air box to verify the hose was connected. As far as I can tell the hose is connected. Will it help to disconnect the negative battery cable? Do you know will that clear the codes and turn the check engine light off?

Thanks,

Germex)

Ok in follow up to my above message, I went to Auto Zone again and had the same OBD reading (P0440 and P0446). Checked the hose off the airbox and it is attached. Put a new gas cap on. Reset the the check engine light and it was fine for a few days. Filled the car with gas yesterday and light came on again later that day.

Not sure what else to check? Does anyone have experience with these two code readings. Could it be a bad tube or seal, bad vacuum hose, something in the charcoal canister, Vapor pressure sensor??? Just looking for some input on what to check next.

Any help would be greatly appriciated.

Thanks,

Germex

With all the hoses under the hood that can cause problems, let's make sure we are talking about the same hose. The one I am referring to is connected to a metal tube that comes up along the fender well under the brake master cylinder and in front of the fire wall. It is not easy to see and you have to have the top of the air cleaner off and your face has to be directly above the master cylinder and a bit to the left as you are looking towards the passenger compartment. It helps to have a flashlight. My girl friend had her oil changed again last week and last weekend I had to reconnect the hose.

[Germex]

Did you clear the codes? I disconnected the neg battery cable for 5-10 minutes and that worked like a charm.

Check the hose again, make sure it's clipped on.

Yes I had the person at Auto Zone clear the codes and I put a new gas cap on. After they cleared the codes and I put a new gas cap on it was fine. I used the car for about 2 weeks and then filled the tank with gas about 1 week ago and now the vehicle is at about a half of tank of gas and the light came on again. I just went out and checked the hose again. I even took the top off the air box to verify the hose was connected. As far as I can tell the hose is connected. Will it help to disconnect the negative battery cable? Do you know will that clear the codes and turn the check engine light off?

Thanks,

Germex)

Ok in follow up to my above message, I went to Auto Zone again and had the same OBD reading (P0440 and P0446). Checked the hose off the airbox and it is attached. Put a new gas cap on. Reset the the check engine light and it was fine for a few days. Filled the car with gas yesterday and light came on again later that day.

Not sure what else to check? Does anyone have experience with these two code readings. Could it be a bad tube or seal, bad vacuum hose, something in the charcoal canister, Vapor pressure sensor??? Just looking for some input on what to check next.

Any help would be greatly appriciated.

Thanks,

Germex

With all the hoses under the hood that can cause problems, let's make sure we are talking about the same hose. The one I am referring to is connected to a metal tube that comes up along the fender well under the brake master cylinder and in front of the fire wall. It is not easy to see and you have to have the top of the air cleaner off and your face has to be directly above the master cylinder and a bit to the left as you are looking towards the passenger compartment. It helps to have a flashlight. My girl friend had her oil changed again last week and last weekend I had to reconnect the hose.

Hi RonRX300,

Thanks for the reply. I am almost positive I have checked the correct hose. Just to be sure when you lift the cover off the air cleaner it is attached to the back of the cover of the air cleaner and a also to the metal tube that comes up from along the fender back to the fire wall. You for the most part cannot lift the cover off the air cleaner very far if it is connected to the metal tube. I have opened the gas cap again and also noticed there isn't that swooch sound so it could possibly be something else in the evap system.

Thanks and I will keep digging into it further. Don't want to give up yet and take it to a mechanic.

Germex

[RonsRX300]

Did you clear the codes? I disconnected the neg battery cable for 5-10 minutes and that worked like a charm.

Check the hose again, make sure it's clipped on.

Yes I had the person at Auto Zone clear the codes and I put a new gas cap on. After they cleared the codes and I put a new gas cap on it was fine. I used the car for about 2 weeks and then filled the tank with gas about 1 week ago and now the vehicle is at about a half of tank of gas and the light came on again. I just went out and checked the hose again. I even took the top off the air box to verify the hose was connected. As far as I can tell the hose is connected. Will it help to disconnect the negative battery cable? Do you know will that clear the codes and turn the check engine light off?

Thanks,

Germex)

Ok in follow up to my above message, I went to Auto Zone again and had the same OBD reading (P0440 and P0446). Checked the hose off the airbox and it is attached. Put a new gas cap on. Reset the the check engine light and it was fine for a few days. Filled the car with gas yesterday and light came on again later that day.

Not sure what else to check? Does anyone have experience with these two code readings. Could it be a bad tube or seal, bad vacuum hose, something in the charcoal canister, Vapor pressure sensor??? Just looking for some input on what to check next.

Any help would be greatly appriciated.

Thanks,

Germex

With all the hoses under the hood that can cause problems, let's make sure we are talking about the same hose. The one I am referring to is connected to a metal tube that comes up along the fender well under the brake master cylinder and in front of the fire wall. It is not easy to see and you have to have the top of the air cleaner off and your face has to be directly above the master cylinder and a bit to the left as you are looking towards the passenger compartment. It helps to have a flashlight. My girl friend had her oil changed again last week and last weekend I had to reconnect the hose.

Hi RonRX300,

Thanks for the reply. I am almost positive I have checked the correct hose. Just to be sure when you lift the cover off the air cleaner it is attached to the back of the cover of the air cleaner and a also to the metal tube that comes up from along the fender back to the fire wall. You for the most part cannot lift the cover off the air cleaner very far if it is connected to the metal tube. I have opened the gas cap again and also noticed there isn't that swooch sound so it could possibly be something else in the evap system.

Thanks and I will keep digging into it further. Don't want to give up yet and take it to a mechanic.

Germex

Sounds like the problem could be elsewhere. Too bad, that was an easy fix.