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Discussion Starter #41
Well, I decided to try a new intake that I got for cheap... its pretty nice. I moved the VSV at the airbox and replaced the two vacuum hoses at the VCV. I think airflow is much better. I found I had a crack/leak in the old airbox. Could that have caused a problem here?

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Unfortunate. There must be a leak somewhere in the system that hasn’t been tracked down yet.
 

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Discussion Starter #44 (Edited)
Ok, I capped the vent at the canister and smoked the system again. Could not see any leaks. It was able to build pressure. Applied power to all three VSV and they all "clicked". I am trying to think of the remaining possibilities.... Tank leak, filler neck, new gas cap bad, VSV stuck open, vapor pressure sensor bad. How should I verify the VSV or sensor is bad?

Can I delete that little EVAP black box in the lower photo?

Also, P0440 and P0442 have BOTH returned.....

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Is that little black box cracked? Fuel filler neck would be hard to see smoke coming out of it. It could have a bad coupling. Considering all the VSV clicked when you tried them, I wouldn’t think one is stuck open personally.
 

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In theory a bad FTP sensor could cause these codes. However you would sometimes get a P1453 with these other codes pointing you to a faulty FTP sensor. I hate EVAP codes in general. They can be easy or downright impossible to figure out at times.
 

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Discussion Starter #50
When you checked the vsv's did you blow or suck to make sure they do not leak?
I only checked to see if they clicked, was not sure how to setup a test to see if they leak across or are stuck in position. They all made a strong click sound, I just powered them with a 12V battery.
 

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Discussion Starter #51
In theory a bad FTP sensor could cause these codes. However you would sometimes get a P1453 with these other codes pointing you to a faulty FTP sensor. I hate EVAP codes in general. They can be easy or downright impossible to figure out at times.
These EVAP problems are extremely frustrating. I wish I could figure it out or disable the codes for these errors only. Don't really want to spend more money guessing on this issue.
 

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With no scanner this makes it harder to diagnose the vapor/fuel tank pressure sensor. Basically it should read vacuum with the purge valve on and vent closed. It should read no pressure with the gas cap off. The sensor is what passes the onboard monitors so a stuck signal is very possible. As far as the solenoids, a click doesn’t mean much.
 

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I only checked to see if they clicked, was not sure how to setup a test to see if they leak across or are stuck in position. They all made a strong click sound, I just powered them with a 12V battery.
Take the solenoid in your hand and blow through it. Then activate it. It should seal and pass air as you activate and deactivate.
 

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Discussion Starter #54 (Edited)
With no scanner this makes it harder to diagnose the vapor/fuel tank pressure sensor. Basically it should read vacuum with the purge valve on and vent closed. It should read no pressure with the gas cap off. The sensor is what passes the onboard monitors so a stuck signal is very possible. As far as the solenoids, a click doesn’t mean much.
The only thing I was testing was if they reacted to any voltage. They did, that's all I could do with that limited test

The codes come on independently of each other and usually at intervals of 250-350 miles
 
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