repairman54

Need it to self test and go OK for state inspection. I can read all 4 code families and no evap codes are being set. Been through several test cycles, correct fuel levels and drive modes.
I'm thinking purge valve, vent valve or something in the EVAP has failed but not enough to set a hard code yet stopping self test.
Any hints or experiences would be appreciated before getting into the parts swapping routine which I'm not a fan off. BTW I'm a experienced wrench with Alldata access.

tech2

what vehicle?
it may be an ambient temp issue. Some designs will not run the evap monitor if ambient temp is to low. My fca vehicle i know for a fact will not run the evap monitor in winter. Ever wonder why you rarely get evap leak codes in winter. moitoring pressure changes in cold climates could skew testing results.Call the inspection station and confirm if they will give a conditional pass for evap monitor not complete. this info may even be listed on the testing website.

repairman54

'11 5.3 Tahoe in my sig. vehicle list.
Alldata only mentions IAT temp. min. of 36F for tests. Coldest I've been is in the forties and been doing drive test routine in the fifties. I see your point on some systems not running due to vapor pressure differences of winter blend fuels.
I've got to the end of Jan. to get a legal windshield sticker, would like to do it ''right'' though. I'm in NJ and with the virus thing every state worker is in snail mode. I'll check on the conditional if needed, thanks for that tip.
Scanner is showing some purge solenoid and vent valve readings but in red background as it will normally show green background when readings are good yet no EVAP fail codes in any of the code families. That's the only odd thing I can pick up when doing scans. Shorted or open should set a code. Can't find any specs for ohm's on valve solenoids to even check them for partial shorts or connection issues.

tech2

the monitor won't schedule a test so it won't pass/fail. Doesn't mean the evap system won't purge...just won't leak test. the system is working normally.
if the system had a circuit fault a code would set immediately. the evap leak monitor is different from a comprehensive component monitor.

tech2

you don't seem convinced.

Can I Pass the Smog Check if the EVAP Monitor is Incomplete? (smogtips.com)

if cali allows it I'm sure everywhere else will too. you can't make the system do something its not designed to do.

repairman54

Thanks for the info. Just need to be correctly armed for the DMV pissing contest.

repairman54

Well 1500 miles later and no EVAP monitor ready. Failed again, boss man at the inspection station says NJ no longer give a pass on one monitor not being ready. Basically I have to keep my inspection attempt papers on hand in case I get stopped to get off with a warning until the weather warms up and it self tests per the inspection station Mgr. .
He said I'm not alone on this with other GM and Dodge owners but SP has been lax on overdue sticker with the virus deal.
Just sharing my adventures with the group.

tech2

Crazy situation. thanks for the update. note to self...don't move to NJ!lol