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Evaporative System - Incomplete

IndeedSS

SS-DD Level Member
Inspection time is coming up and I need to figure out why everytime I check the DTC'c my Evap System shows as incomplete.

I clear the codes and that resets all of the testing but the Evap system always comes back to Incomplete...you can't pass inspection with an Incomplete.:th_angry2:

I think I may disconnect the battery to see if the PCM just needs to be "reset", but I have my doubts that this will work.
 
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I don't have to worry about codes because my car doesn't get inspected for emissions or codes.

But I believe you can set the codes to "Non-reporting" with your tuner. Then, even if something is wrong, it won't even report it to the PCM, so nothing is stored. If you just turn off the code, the PCM will still store the code, but just won't turn on the light.

Try changing the said codes to non-reporting, clear everything, and make sure you drive 150-200 miles before inspection. All should be good.
 
I'll give it a shot. I was worried since this is an item that is hard coded and with either read incomplete, complete, or NA. Anything but complete and you fail.
 
have you removed any parts from the evap system??

nope...everything is connected. Back when the N* was installed the evap line was installed on the blower vaccum port. It was throwing a P0455 for a while, but that no longer happens. Stock TB is back on with a plug on it's evap port and the evap line is still connected to the blower.
 
nope...everything is connected. Back when the N* was installed the evap line was installed on the blower vaccum port. It was throwing a P0455 for a while, but that no longer happens. Stock TB is back on with a plug on it's evap port and the evap line is still connected to the blower.


you moved the evap line to the blower vac port when you installed the N* and didnt move it back to the tb when you went back to stock, only capped off the original vac port?

is that what i'm reading?
 


put it back the way it came from the factory, mang!

I would but the line won't fit the stock location any more. Besides isn't the vaccum relatively the same at the TB as it would be at the blower triple tree?

I'm not getting any codes, the system test just isn't completing.

I downloaded a GM drive cycle walkthough today. I'm going to give it a shot to see if it will complete the testing.
 
its likely it would be the same, but there is obviously some reason why its not completing the test, and fixing the location of the evap hose would seem the cheapest and easiest thing to do first.
 
its likely it would be the same, but there is obviously some reason why its not completing the test, and fixing the location of the evap hose would seem the cheapest and easiest thing to do first.

A replacement hose was ordered from paceperformance, however, the N* may wind up going back on. No reason the stock location couldn't be tested first.

After some searching, I was surprized by the amount of people that had this problem.
 


A replacement hose was ordered from paceperformance, however, the N* may wind up going back on. No reason the stock location couldn't be tested first.

After some searching, I was surprized by the amount of people that had this problem.

the non-complete test in general, or the non complete test after N* ?
 
I would just tell the pcm not to report it if i were you. You can do that with a tuner. Just remember what number the code is.
 
I'm not getting a code.


Then what do you mean by:

everytime I check the DTC'c my Evap System shows as incomplete.

I read it as, you check your DTC (Diagnoistic Trouble Codes), and a code shows a problem with the Evap system. That it is not testing completely. So how can you check your DTCs, and something shows up as wrong, but have no DTC?

I am confused.
 


When you pull up your DTC's those are listed as Pxxxx, Bxxxx, Uxxxx, if you have any codes set. As part of the DTC's, there are tests that are performed on the cat, egr, evap systems. They show as Completed, Incompleted, or NA. You can have no codes and still have one of these hard coded systems tests show as Incomplete and you will fail your emmissions test.

Car is at the body shop so I cant do a screen shot of the HPTuners DTC window, but here is the info saved from the last check.
 

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Did you ever delete the evap codes from your PCM? Or turn them off I should say? Or do you have a ZZP or DHP PCM? Did you start with one of their PCMs?

If all the codes are set correctly, and the evap system comes up as incomplete, it should produce a DTC, letting the driver know there is something wrong.

My guess is somewhere along the lines, this DTC was turned off, but only turned to keep the SES light off. And you need to find that, and set it to non-reporting. But that is just my guess.
 
Did you ever delete the evap codes from your PCM? Or turn them off I should say? Or do you have a ZZP or DHP PCM? Did you start with one of their PCMs?

If all the codes are set correctly, and the evap system comes up as incomplete, it should produce a DTC, letting the driver know there is something wrong.

My guess is somewhere along the lines, this DTC was turned off, but only turned to keep the SES light off. And you need to find that, and set it to non-reporting. But that is just my guess.


Nope everything is stock and I have my factory installed PCM in the car. I've checked every code that is Evap related and all of them are set to Enable and the reporting turned on. HPTuners has a nice compare feature where you can look at two bins at the same time with options to display the similaries or differences. or actual value differneces between the cells in a table...side tracked for a minute.:)
 
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