[SOLVED] Ca Smog, Secondary air system not completing, no light, pump comes on, no backflow...

[Yukongreed]

Trying to smog my 2001 yukon out here in Ca. Secondary air system wont complete its check on computer. Theres no check engine light on, ive tried the cold start with everything running till warmed up, ive preformed two drive cycles. Took it to my buddys shop he said everything is as it should be valves not backflowing no codes etc only thing he couldent confirm was that air pump was coming on at cold start which I can confirm it is...


Any tips or tricks? Im thinking inspect/replace pump maybe its low flow? any help appreciated!

 

[Scottydoggs]

a lot of times some self checks take a long time to become "ready" like evap can take weeks to pass. might just need more time.

 

[Doubeleive]

Trying to smog my 2001 yukon out here in Ca. Secondary air system wont complete its check on computer. Theres no check engine light on, ive tried the cold start with everything running till warmed up, ive preformed two drive cycles. Took it to my buddys shop he said everything is as it should be valves not backflowing no codes etc only thing he couldent confirm was that air pump was coming on at cold start which I can confirm it is...


Any tips or tricks? Im thinking inspect/replace pump maybe its low flow? any help appreciated!

pull the line and verify the pump is actually pumping air, pretty sure you can just jump the pump with 12v just only let it run a few seconds at a time because it is designed for intermittent use only.
check the air line for leaks (spray with soap&water mix)
if pump fails, grab a used one from the junkyard but they will only be found on 00/01

 

[Marky Dissod]

a lot of times some self checks take a long time to become "ready" like evap can take weeks to pass. might just need more time.

If the fuel tank is over 3/4 Full or under 3/4 Empty, yes, it can take way too long to 'get ready'.
Get as close as possible to 1/2 tank, that speeds up how quickly the EVAP readies itself.

As for the stupid AIRpump, which was effectively unnecessary for later GMT800s,
just get it tuned out 'Error Not Reported', and you'll never waste another dime on it ever again.

 

[Doubeleive]

My money is on, it's not pumping air even though it turns on

 

[Yukongreed]

My money is on, it's not pumping air even thou

The pump is in fact blowing strong! What’s the little distributer after the pump could that be clogged/malfunctioning? And or off of that there is a little hose that goes to a wiring harness?

 

[Doubeleive]

The pump is in fact blowing strong! What’s the little distributer after the pump could that be clogged/malfunctioning? And or off of that there is a little hose that goes to a wiring harness?

I believe there is also a check valve or two, (check those for proper operation) man it's been years just going off of memory
check the relay
I would check for leaks, and I believe unless I am wrong that the pump should come on almost if not every time you start the vehicle not just when it is cold or intermittently
and it should run for xxxxx seconds. (refer to manual for exact time)
if you can I would just ahead and try to grab one from a junkyard anyway and swap it out to see if anything changes it's not hard to do.
keep the old one in case nothing changes

 

[Doubeleive]

I think when mine had failed it was not coming on as much as it should, I think it was intermittent.

 

[Doubeleive]

this thread probably has some good info, one dated jan 25th talks about engine temp not getting warm enough to make it run the secondary air test

https://www.gm-trucks.com/forums/topic/173303-secondary-air-injection-monitor-will-not-run/

 

[Marky Dissod]

Just get a tune that permanently disables the AIRpump; problem solved forever & ever.

 

[Scottydoggs]

Just get a tune that permanently disables the AIRpump; problem solved forever & ever.

you cant get away with that in CA any more. they can tell if codes are set to not report. and then they fail you.

 

[Marky Dissod]

you cant get away with that in CA any more. they can tell if codes are set to not report. and then they fail you.

Sounds like a half@$$'d 'tune'; tunes by PcmPerformance are still passing in CA.

 

[Scottydoggs]

Sounds like a half@$$'d 'tune'; tunes by PcmPerformance are still passing in CA.

you can tune cars still. but you cant delete codes. im sure theres a way to make things pass with out deleting codes tho. no idea how you might do that to a smog pump tho.

 

[Marky Dissod]

you can tune cars still. but you cant delete codes. im sure theres a way to make things pass with out deleting codes tho. no idea how you might do that to a smog pump tho.

So CA has gone beyond just checking checksums & CVNs? HOW?

 

[Scottydoggs]

So CA has gone beyond just checking checksums & CVNs? HOW?

they can now tell if emissions codes are deleted. with a simple scan as i understand it.

 

[Yukongreed]

My smog guy did mention something about getting something erased or cleared... I didnt follow up at the time I should have, so im under the assumption that there is a backdoor to getting secondary air pump completion through to pass smog without it actually.. gosh damnit this is turning into a pain in the ass reg was due Mar i paid it but no stickers-

 

[Doubeleive]

My smog guy did mention something about getting something erased or cleared... I didnt follow up at the time I should have, so im under the assumption that there is a backdoor to getting secondary air pump completion through to pass smog without it actually.. gosh damnit this is turning into a pain in the ass reg was due Mar i paid it but no stickers-

that thread I linked mention something about the tech2 being able to complete it but I never personally tried anything like that generally that kind of stuff is NOT TRUE.
it could maybe be the case for a secondary pump, "maybe" if you can someone that has one. I do but I am in nor-cal

 

[Yukongreed]

I’ve got my check valve out that’s after the pump, could it be stuck closed? When I blow into it from pump inlet it does not blow through how does this thing open? I can press it up from bottom and create flow- got it opened up just a spring and orange gasket.. def has a little debri around gasket lip.. cleaned but once reassembled still no flow I can’t imagine my pump is blowing harder than I can with pressure..

 

[Doubeleive]

I’ve got my check valve out that’s after the pump, could it be stuck closed? When I blow into it from pump inlet it does not blow through how does this thing open? I can press it up from bottom and create flow- got it opened up just a spring and orange gasket.. could I run it without gasket to get this thing to pass?

not sure, but that valve looks like it is vacuum activated, so suction on the small line would allow it to open and let pump air in thru the larger pipe, trying to blow thru the larger pipe likely wouldn't do anything unless the valve is vacuumed open
so you would need to connect it to a vacuum line and then try to blow thru it.
there is a tool to test (mighty vac) it's but not worth running out to get one, you should be able to connect to the line that was on it or the one that goes from the air intake to the intake with the engine running. if it has enough vacuum.

 

[Yukongreed]

not sure, but that valve looks like it is vacuum activated, so suction on the small line would allow it to open and let pump air in thru the larger pipe, trying to blow thru the larger pipe likely wouldn't do anything unless the valve is vacuumed open
so you would need to connect it to a vacuum line and then try to blow thru it.
there is a tool to test (mighty vac) it's but not worth running out to get one, you should be able to connect to the line that was on it or the one that goes from the air intake to the intake with the engine running. if it has enough vacuum.

Ok ran it without little vacume hose before i saw your reply and very little flow was coming through valve from pump, attached small vacume line from engine to valve and it flowed much better. Would that confirm that my solinoid is functioning to allow vacume from small line? Will try running it it for awhile it was pretty dirty around gasket inside