EVAP emissions monitor not ready

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This is about my Pilot:

About 600 miles back, I disconnected my battery to clean up the terminals and (as expected) all the OBDII readiness monitors got reset. Fast forward to today- I went in for a state inspection and the printout said all monitors were ready except for EVAP. I still passed since the EPA allows for one unready emissions monitor during testing.

How long does it typically take for the EVAP monitor to get ready? My driving is 80% city but I've had a few 30+ mile trips on the highway. I'd think that would be enough for the EVAP test to run.
 
Originally Posted By: mclasser
This is about my Pilot:

About 600 miles back, I disconnected my battery to clean up the terminals and (as expected) all the OBDII readiness monitors got reset. Fast forward to today- I went in for a state inspection and the printout said all monitors were ready except for EVAP. I still passed since the EPA allows for one unready emissions monitor during testing.

How long does it typically take for the EVAP monitor to get ready? My driving is 80% city but I've had a few 30+ mile trips on the highway. I'd think that would be enough for the EVAP test to run.


Probably not time sensitive more than likely a $500 trip to the dealership sensitive!
 
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On most vehicles the EVAP readiness tests won't run until the fuel level is between 3/4 and 1/4 full. Also search around for a Honda specific drive cycle that can be followed so the tests can be completed faster. A rare case would be a bad EVAP component (fuel tank pressure sensor, purge valve, etc) that can prevent the tests from running.
 
EVAP is tricky. It doesn't have to do as much with driving as other factors. Most OEM's want the fuel tank between 3/4 and 1/4 for it to even run the overnight leak down test. You also have to drive it every day or two or the tests will time out.

I have driven close to 800 miles with a tank that had a rust hole on the top big enough to stick your finger through and not had it run the diagnostic, I didn't meet the enable criteria. There is one route I can drive near my house that will set the code almost every time if it was going to fail, it has just the right mix of things.

It's likely you didn't have the right mix of conditions on your trips for the full diagnostic to run. I wouldn't worry about it for the time being.
 
Originally Posted By: mclasser
This is about my Pilot:

About 600 miles back, I disconnected my battery to clean up the terminals and (as expected) all the OBDII readiness monitors got reset. Fast forward to today- I went in for a state inspection and the printout said all monitors were ready except for EVAP. I still passed since the EPA allows for one unready emissions monitor during testing.

How long does it typically take for the EVAP monitor to get ready? My driving is 80% city but I've had a few 30+ mile trips on the highway. I'd think that would be enough for the EVAP test to run.


What are the EXACT parameters as per FSM to complete that particular monitor to readiness status?

Now, that is not to be snarky.. Most people (when it comes time to be inspected) they reset the lights and drive around, though if the exact right conditions are not met, it may not ever come into readiness status. Sometimes, hey, sure, it will set. Sometimes it will not..
 
Stating the obvious:
If the EVAP is good then eventually the code will go away which means it becomes "Ready" and DTC light is off.
If the EVAP is bad then it will continue to become a code and "Not Ready" status continue.

Unfortunately, driving cycle depends on the car mfg, in this case is, Honda.
You may want to ask in the Honda forums see if anybody knows.

Did you erase a code because of DTC light before the inspection?
 
Need about a half tank of gas. Do some mixed driving for 30 min. Park. Next day do some mixed driving again. Mine likes to pop on at low speed oddly enough. It's the code for very small leak and we don't have emissions in FL so I live with it
 
I would fill it full of gas, then reset it by pulling the battery for a couple of minutes.

Drive it until the tank of gas is down to at least 1/4 left (3/4 Empty).

If it isn't ready then book an appointment with the dealership.

The reason I say reset the battery again is because I have seen ECU's do weird things when the battery is reattached because it gets improper voltage for a minute or two until the connection is tightened up.

Good Luck
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Toyota EVAP cycle won't run if the temp is too low. Less fuel vaporization at low temps throws off the vapor pressure requirement. In my state TWO monitors can by "not ready" and the OBDII test can still be run. If you know your EVAP system is not working properly you can work around the smog test by NOT having that monitor ready, by paying attention to the weather.
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Too many folks whose cars are running well get jerked around by sensor problems... meanwhile I see S Boxes on the road every day laying down clouds of smoke. The stealers rub their hands together when someone shows up with a sensor problem.
 
Originally Posted By: StevieC
I would fill it full of gas, then reset it by pulling the battery for a couple of minutes.

Drive it until the tank of gas is down to at least 1/4 left (3/4 Empty).

If it isn't ready then book an appointment with the dealership.

The reason I say reset the battery again is because I have seen ECU's do weird things when the battery is reattached because it gets improper voltage for a minute or two until the connection is tightened up.

Good Luck
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BAD information.

If he resets and clears the ECM then he is back to square one and waiting even longer. It is simple- the test WILL run when the right conditions are met. Keeping the tank above a 1/4 and less than full and doing extended idling will help speed the process up often times. Best bet, as mentioned is to research HONDA's criteria in their FSM and duplicate otherwise, keep driving and wait.
 
If it's not ready in 1 tank of gas then it's never going to be ready. We have smog testing where I am so I'm experienced with this sort of problem.

Not bad information, based on previous experiences with "Monitors Not Ready"

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Instead of pulling the battery and resetting everything and back to square one, would a OBD II scan tool read and reset just the one problem code (everything else goes on as usual), and drive on a while under ideal conditions to see if it comes back? Just asking - I dunno...
 
It will but it could be stuck in a loop which I have seen first hand before with codes that keep appearing or emission monitors not showing ready after prolonged periods of time.
 
If it's not setting a trouble code & your able to pass OBD emissions testing.....I don't see the issue here?

I would think your Pilot is still under Emissions Systems warranty, Take it to the dealer if it bugs you that much!

Without a good scan tool to check for "pending codes" or "trip counters" & bi-directional controls to do some functional tests.....The only answers your going to get are shot in the dark guesses
 
Originally Posted By: StevieC
If it's not ready in 1 tank of gas then it's never going to be ready. We have smog testing where I am so I'm experienced with this sort of problem.

Not bad information, based on previous experiences with "Monitors Not Ready"

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Sorry, But....Your theory doesn't apply to every make & model vehicle. Also realize different regions & countries have different software calibrations that effect this.
 
Just to be clear, I DON'T have a CEL, nor did I clear one in the past by disconnecting the battery. Like I said, I was only cleaning the terminals up. I'm talking about the EVAP readiness monitor, which is one of several monitors looked at when a shop plugs in their OBD II scanner during an emissions test.

I'll check out the FSM but I'm not sweating it. I was just curious about the conditions needed to trigger the test. In the end, my car passed so I'm good
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Originally Posted By: clinebarger
Originally Posted By: StevieC
If it's not ready in 1 tank of gas then it's never going to be ready. We have smog testing where I am so I'm experienced with this sort of problem.

Not bad information, based on previous experiences with "Monitors Not Ready"

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Sorry, But....Your theory doesn't apply to every make & model vehicle. Also realize different regions & countries have different software calibrations that effect this.


Did I say it applied to every make and model? No I didn't. Just that from past experiences this is what I would try.

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Follow the drive cycle. Don't fill the tank to full for a couple times. Keep it between 1/4 and 2/3. and most importantly don't worry about it. The evap system doesn't effect anything just captures some fumes.
 
If the CEL isn't on and it passed the emissions test...why do anything? It's not going to impact driveability or cause any damage. The only thing I'd do is...
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