Djpoint

Here we go again. Bought 02 rx300 10/19. 137,000 miles. I have had nothing but cel codes. Cat 02 sensor, front a/f sensor, knock sensors and harness, maf sensor, gas cap, air intake hoses had holes and missing clamps. All have been replaced. After driving 2000 miles, evap still not ready. Just today I got 3 pending dtcs. 440,441,446. Scanner says evap leak test pass. Lexus told me a few weeks ago that breather hose had holes in it near canister. They said i might smell gas fumes, which I don't. Could this be the culprit? Apparently I had some mice living in vehicle when it was at auction. I pull out fiber shreds from moonroof when I close the sunshade. Plus i found an old nest in the cabin filter.. Also wires at the DrL relays were chewed on. Lexus didn't tell me about a possible code. Could the breather hose be why the evap still is not ready? Any ideas would greatly be appreciated.

salimshah

Please keep in mind, everything is not monitored by OBD. There is a minimum standard established back in '95 and each manufacturer has some advanced monitoring options and some of which are accessible by their proprietary readers and or additional diagnostic port(s).

Bit confused by 'not ready'. I would expect a 'fail' as 'not ready' means not enough information has been accumulated [typically right after 'reset'].

You can have the 'smoke test' done to establish leaks. Proper equipment produces non-combustable smoke at low pressure. DIYers reach out for carb cleaner and listen for increased RPM as the carb cleaner is sucked in [The down side of this test is that the carb cleaner is highly combustible ... I do not recommend this]. Another way is to light up a cigar and blow the exhaled smoke into the vacuum line [smoking is injurious to health] but the good thing is that the smoke is non-combustable. Some one has to really trace the rising smoke.

Once you get past the piping, end clamps, broken nipples you get in the realm of wiring and sensors.

Last resort is pay the piper [good mechanic or dealer]. Let them diagnose for a fee and then make the choice of how to handle the repair cost. Talk to the shop before hand and see if they can roll the diagnostic fee into the full repair.

I have not used the county help, but here in Texas, the county advertises assistance for emission repairs.

Salim

PS: I once heard of a case where the leak appeared when the engine would tilt under toque and when it was left to idle, the break would seal again. Remember to gently tug each connection point as at times the break is so perfect that naked eye does not catch it.

Djpoint

Thanks for your reply. Evap readiness means there are no current docs but can not get inspected because of "readiness" and now I have pending dtcs on scanner which might eventually throw a Cel.

Fit1too

The issue has to happen twice before the check engine light illuminates. I agree with salimshah about taking it to a good mechanic. I've had a P0440 issue since I purchased my 2000 RX. I've inspected vacuum lines, tested VSVs, had it smoke tested, replaced the charcoal canister, gas cap, etc. The light still comes on every couple of days and I turn it right back off because I don't want lights illuminated on the dash. You get accustomed to it and then a warning light comes on signaling a problem, it's ignored and disaster follows. We're in Texas this weekend teaching and the light hasn't come on once during our trip. I've researched and studied the issue quit a lot using the forum and the Internet, but I am limited on my abilities and test equipment. I've found conflicting information as well. Too much to go into now. I am going to have my mechanic look into it when we get home because I am tired of fooling with it. Never had a car with a check engine light issue that I couldn't fix. Oh well, a wise man knows when to throw in the towel.

Androman

Its the overfill check valve on top of the gas tank. its plastic and they always fail.

Fit1too

When the overfill check valve fails does it cause issues when pumping gas?

Djpoint

Just had it at toyota. The holes in the vapor hose being chewed by mice are most likely causing it. Gonna change that Wednesday and see if that clears it. Fingers crossed maybe thats why after a month and 1500 miles of driving the evap is still not clearing"readiness" The pending dtcs 440,441,446 just popped in 3 days ago. But no cel yet

Djpoint

Well theres most likely the culprit. Po440,441,446 pending codes. Mice chewed vapor hose which attaches to canister and to gas tank. New part on Tuesday

Fit1too

When you drop the tank, make notes and take pix please! I should would appreciate it! Those mice are nasty creatures.

Djpoint

Didn't have to drop tank. Its a 2 piece. A squeeze disconnect before tank and a disconnect at canister. This rx sat at auction probably in a grass field for awhile. Had a nest in cabin filter as well

Fit1too

You have to ask yourself, "why are they eating plastic?" Copper wires I can see, (we need copper in our diet), but plastic!

BudTC

I've been told it's because they like the taste due to the type of oil they use to make the plastic.

Djpoint

After replacing vapor hose that mice had chewed and 150miles of driving, the evap is now ready"readiness" Hopefully it'll stay that way

salimshah

"Channel ready" means enough data has been accumulated to determine pass/fail since a reset event. Pass/fail ~ No-codes/error_code comes after the channel is ready.I hope your RX remains error free. I

Salim