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I have a 97 Rav4 absolutely had no prior problems, So I had some battery acid build up on my battery so cleaned the post waited a week drove to work (130 Miles) took it in to smog the car passed the Emissions Test but failed the I/MS Cat/Evap part saying its Not recognizing the Cat and the Evap was told to drive car so I have drove the car another 350 miles on top of the 130 aprox 480 miles and it stills says the same thing. And there is NO check engine light on or codes. I even bought an updated code reader just incase the shop was lying
Area driven if you know Hwy 50 - Placerville, Ca to Lake Tahoe Ca and back, next day Placerville,Ca to Citrus Heights Ca and back I have been from Sea Level to 7,000 Ft in elevation
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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If fuel level and air temp requirements are met (the evap test tries to run after a cold start, in park, at idle, air temps between 40-75 deg. F, and fuel level not under 1/4, and not over 3/4 full), try letting her idle for a couple of minutes after a cold start to giving her a chance to run the monitor test.

If its failing the evap test, and that's what's throwing codes, then there are several things that could be causing a leak in the system.:

1) A loose or bad gas cap seal
2) Evap (charcoal) canister -
2a) Loose hose clamps, on the filler pipe (between gas tank and gas cap). On my RAV4 the filler hose was badly deteriorated, it wasn't leaking... yet but it would have soon.
2b) Damaged tubing /piping
2c) A bad O-ring seal between connections
2d) An improperly tightened "test port" cap (green colored) by the purge valve
2e) A faulty "test" valve.
2f) Even a damaged or punctured canister

Resist the urge to "clear" the codes, thats right, dont clear it. Once the problem causing the code is fixed, the light will soon turn itself off. The code stored in "memory" will not cause you to fail an inspection, only active codes will, or excessive number of "not ready" monitors. Also every time you clear the codes all readiness monitors are reset to "not ready", and have to run again. The cat monitor should complete after a few cycles at light highway speeds. The evap is more picky. on some vehicles, it might not complete for a long time...

Think about all the rubber hoses, belts, and bushings on a 20+ year old car, that they are breaking down, rotting, getting hard, cracking, and just causing annoying problems. Replace them all or have problems.
 

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As stated above... I know those roads well... the catalyst monitor should of set. Evap needs 3/4 tank of fuel and should sit overnight for tank pressures to change. Do not reset monitors as eodgator stated above. What code do you get if any?
 

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Discussion Starter #4
There is No Codes and No Check Engine light- They run a check on your computer and the computer recognizes everything but the Cat and the Evap. The car actually passed the Emissions Test of the smog test but Failed due to the computer not recognizing the Cat and Evap.
How I knew about the battery was I went to start it and it wouldn't start so I lifted up the red cover to see battery post with acid on it
 

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I just worked on a friend's '03 Civic (a months long saga) trying to get it thru CT emissions. And I agree with the others don't do any resets or disconnect the battery as that makes the monitors start over. I swapped cars and put a lot of miles on her's watching and waiting for the monitors, 6 as I recall, to complete. Some would complete almost immediately or within a few miles. The Cat and Evap took the longest with the Evap coming in last. The only concession I made to it was buying a new fuel cap. I finally gave her the Civic back loaned her my scanner with instructions to watch for the incomplete monitors to go to 0 and then drive right to emissions. She called me the next morning saying she saw 0 and it passed.
Two tips: It's my conclusion that the Evap requires several cold starts rather then a lot of miles since she never drove it more than 10 miles on any one trip and the Cat apparently needs secondary road speeds, say in the 40-60 mph range.
 
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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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There is No Codes and No Check Engine light- They run a check on your computer and the computer recognizes everything but the Cat and the Evap. The car actually passed the Emissions Test of the smog test but Failed due to the computer not recognizing the Cat and Evap.
How I knew about the battery was I went to start it and it wouldn't start so I lifted up the red cover to see battery post with acid on it
I gave you more than you really needed for just a "not ready" condition on the CAT and EVAP monitors. What happened when you disconnected the battery to clean it is that the monitors reset and had to reinitialize. Most reinitialize very quickly, however the CAT and EVAP are usually the last to initialize. The EVAP can take a long time to initialize if all the conditions are met, it will not initialize if the conditions aren't met.

If fuel level and air temp requirements are met (the evap test tries to run after a cold start, in park, at idle, air temps between 40-75 deg. F, and fuel level not under 1/4, and not over 3/4 full), try letting her idle for a couple of minutes after a cold start to giving her a chance to run the monitor test. This may have to be repeated several times, remember it has to be a cold start each time.

If all the conditions are met and it won't clear after repeating this several times it will be time to go down my list I gave you. It usually won't throw a code as long as it cannot initialize.
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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Sorry I kept editing the above, I was trying to make sure it was fully explained.
 

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Discussion Starter #9
Thank you I will give this a try, Its had 10 days of cold starts at idle but it has been a little colder that 40 degrees out when its been warming up thinking maybe its the New gas cap I will stop and get another one just incasse
 

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1999 Toyota RAV4 with 3MZ-FE 6 cylinder engine, camo wrap, OME lift, heavily modded
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The evap box isn't hard to inspect and there aren't that many lines running to it. I replaced all my vacuum lines wth high temp silicon lines, the lines going to the throttle body and the return gas line I replaced with gas line. Never overfill the tank it can ruin the evap cannister and they are costly to replace. A friend showed me how he used a dremel to open it up and change the activated charcoal and used Permatex 85420 Permashield Fuel Resistant Gasket Dressing & Sealant to put her back together. I haven't tried it because I haven't had trouble with my evap cannister.

To change the fill hose and evap hose at the tank, remove the driver's side rear wheel, pull the cover and they're right there. You will need a jack stand to support the car while you work under it.

Good luck.
 

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Discussion Starter #11
Update I put back on the old gas cap and computer has recognized so Evap is now good to go, it but still no Cat
 

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Sorry for such a long wait for a reply. After 1,100 miles finally my computer is recognizing the EVAP but still doesn't recognize the CAT. But after some research I found out in California 1996-1999 you can have one light on and still pass smog, So took car in and PASSED with flying colors
Thank you for all the help
 
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