OBD evap monitor not setting!

[EricF]

I'm officially frustrated and losing patience.

my 06 Saturn Relay 3.5L (same as the chevy Uplander) is making me lose my mind.
last week the check engine light came on. checked code, it was p0171.
Under the hood, the rubber pcv elbow was leaking vacuum.
I replaced it. got my Equus obd scanner, cleared the code.
started the engine, drove around a couple miles, light stayed off.
I drove it over the weekend to get the obd registers to go green light.
i had 4 that weren't ready. I drove 70 miles and 2 of them went green.
the other 2 didn't. I found online somewhere how to register the sensors for GM,
followed it as best I could, there's no possible way to go 55mph then coast to 20 then acccelerate back to 55 again and do it a couple times in California.
Even on Sunday early morning when there's no cars, well there's a whole mess of them!
I was actually afraid I was gonna be run over!

Earlier this evenign when traffic has finally left, I hit the road. went to the hilly area so I could try and coast to 20 and get to 55. I put 65 miles on and the catalyst light is good. the EVAP light still won't set.

Normally I wouldn't really care because it'll eventually set, however due to my procrastination, I have the registration due 3/20 AND worse.. have to smog it too.
I am very sure it'll pass fine, however, in California, all the obd registers/monitors must be set. if they aren't, california thinks you're hiding something and it's and auto fail.

Any ideas what I have to do to get the evap monitor to go green? I'm starting to feel the stress from my procrastination!
The CEL is off, there's no codes lingering, just the amber light staring at me!

Help!

 

[Colt45ws]

The EVAP monitor has pretty strict entry conditions. The tank cannot be too full, nor too low. The car has to have been sitting off at least 6 hours. The fuel level cannot change more than a certain % during the test or it will cancel and start over. The reason is because if it sees the fuel level move a lot it surmises that the fuel probably sloshed which would nullify the test.
I'd top it up to about 3/4, then take it out on to the highway the next morning.

 

[wirelessF]

I had the same issue too when my ScanGuage on my 02 Silverado V8 would read -Not Ready- for weeks. I filled up to 1/2 to 3/4 tank, disconnected the battery overnight to clear the ECU and readiness monitors, and pressed brake pedal several times to clear remaining power. You could try this first thing in the morning. I have a planned route where I could take my time, not frustrate other drivers and complete acceleration/downhill coasting.

Disconnect battery during the night (let ECU go to sleep 20-30 min prior) hit brake to clear power.
Reconnect battery
Idle for 15 minutes (allow engine to fully warm up)
Put it in drive for 5 minutes, reverse for 5 min then in Park.
Go for a gentle neighborhood drive for 30-45 min (Where I would drive to a freeway entrance where it has a downhill grade).
Cross fingers and hopefully its clear, merge onto freeway to above or at 55mph. Downhill coasting will hold or increase speed but don't touch brakes. Injectors will shut off and engine brake. Try to maintain fuel cut-off longer then gas when below speed limit.
Drive for several minutes in neighborhood, go home turn off engine.

Repeat next morning. Try taking a longer neighborhood drive. Readiness monitors should be all Ready before doing the freeway part. Total time for me 4 hours in two days.

 

[eljefino]

I suspect the PCV elbow has nothing to do with the EVAP leak.

They are under an EPA mandate to find a specific sized leak, a hole approx 1mm in diameter. I suspect you have about this size so you're in the "no man's land" of pass/not passing. I'd get a "smoke test" where they pressurize the EVAP system.

You also have to pass rear o2 and catalyst monitors at "about the same time" as EVAP. EGR, too, if you have it. They are unpleasently entangled and prerequisites for each other. I found I made them all click in by using 2nd gear (automatic) engine braking. Actually saw it happen on my scan tool.

 

[yonyon]

The evap monitor can be a tough one. On some cars it just plain won't happen during winter, but you don't have the cold weather thing to worry about so it should be doable. Get the gas tank to around 3/4 full or so and park the car overnight. Start the engine and let it idle for 2 or 3 minutes, then drive around at moderate speeds for a while. Avoid hard acceleration. Park for 8 hours, then drive around again. It should go.

 

[NHGUY]

If this was a 1995 or prior model year,this would not be an issue.

 

[Falken]

This is the reason you have to be careful when clearing codes.

I have a cheap INNOVA scanner and I cleared a misfire code and it wipes out all the completed diagnostic tests that the car has to redo during multiple specific drive cycles.

Some of the emissions tests took FOREVER to complete on my car, months IIRC. And this is for a 2010 Honda Fit.

 

[yonyon]

Many GMs have an evap service bay test. This means that someone with a suitable scan tool can make the evap monitor run pretty much on demand. Fuel level has to be in range and coolant temperature has to be below something like 140F or so at startup, that sort of thing. I'm going to assume your tool doesn't have this feature, but you do have the option of going to a garage if it comes to that.

Your fuel gauge doesn't make wild swings does it? A dirty fuel level sender can keep the evap monitor from running without setting any codes.

 

[Colt45ws]

Originally Posted By: eljefino
I suspect the PCV elbow has nothing to do with the EVAP leak.

They are under an EPA mandate to find a specific sized leak, a hole approx 1mm in diameter. I suspect you have about this size so you're in the "no man's land" of pass/not passing. I'd get a "smoke test" where they pressurize the EVAP system.


Uhhh, yeah, its probably not that. I didnt even see that it was the PCV hose you replaced. Its supposed to be able to find holes down to .040". Its probably failing so its having to retest before itll set a code.

 

[dave180]

Evap also requires you to complete a predetermined number of drive cycles. In addition, it really only functions when the ambient temperature is above approximately 40 degrees.

 

[Vikas]

You get a sticker on that car even with 2 incompletes; go ahead and get the sticker now before check engine light fire again!!

evap needs specific amount of gas in the tank, usually between 1/4 and 3/4; outside of that range it won't run the monitor.

once again, get your vehicle inspected while there is no code and NO MORE THAN TWO monitors are incomplete.

 

[EricF]

Unfortunately in California, all monitors must be set of it's an automatic fail.

The tank had 1/2 tank when I started the process, it's now between 1/4 and 1/2.

All that was bad was the rubber elbow piece that sits ontop of the pcv valve. the hard plastic line was fine. the rubber elbow is new and it's sealed like it should be.
the CEL light has not relit.

Thank You everbody for the advice! I'm going to try everything!

 

[Vikas]

Was not aware that CA is now insisting on all monitors to be completed :-( Also I gave wrong information because I did not realize you had 2006 model; for that year most (other) states allow only ONE incomplete monitor. 2000 and before allows TWO.

At least that was the deal when I did the research few years ago.

 

[EricF]

I talked to my buddy who just got his smog license.
He said cars from 99 and older can get away with 2 monitors not set
cars '00 and newer can have 1 monitor not set.

On a positive note, a shop nearby told me to try his Snap-On Modus and said it should run the diagnostic.
Well after 10 miles of driving and 40 minutes of waiting afterwards, the light set!!!!!!!!!!!!!

My stress level just plummeted!!
Although I know officially I could have gotten away with it not being set, it's now set and I'm not gonna mess with it ever again!
Of course the water pump I believe is starting to seep a little, so the battery will have to come out. BUT.. I'll have a year to reset that light and I won't care!

(doing the happy relief dance now!)