Secondary air injection monitor will not run!

Williamsauls · May 28, 2015

Guys,

I need some help with my 2001 5.3l Silverado. I need to smog test my truck but in Caliornia all monitors must be ready to pass. The only monitor that has not completed is the secondary air injection. The truck is not throwing any codes and there are no drivability issues. I've complete every drive cycle I can find numerous times, including the generic GM drive cycle, none have enabled the secondary air injection monitor. I've driven the truck for at least 2 months and put on 1000+ miles since changing the battery which caused my monitors to reset. Each morning I complete a cold start idle for 2.5 minutes hoping the secondary air will run. Below is a list of items I've inspected or changed in an effort to fix my problem.

Secondary air pump-I tested its operation at startup. The pump enables at startup and pumps air at an acceptable volume. There are no signs of wear or issues with the pump.

Secondary air valve- I tested operation at startup The valve opens and allows air to flow from the pump to the exhaust. There are no signs of wear and all vacuum line were inspected for leaks.

Secondary air check valves- Both valves were inspected and replaced due to carbon buildup. Neither were clogged but I still replaced.

O2 sensors- I replaced both pre cat O2 sensors because both had 100,000+ miles. The O2 sensors have been monitored using a scan tool and no signs of issue have been noted.

I've monitored both pre cat O2 sensors during startup and I can see when the secondary air pump is enabled. Both sensors go lean until the pump is deactivated and closed loop is achieved.

I've monitored engine coolant temp, intake air temp and ambient air temp with my scan tool to ensure all sensors are allowing for a cold start.

Again the truck runs great and has no pending or stored codes. It just will not run the secondary air injection test. I'm no slouch when it comes to wrenching on cars but this one has me stumped! What would be my next option? Does anyone know what sensors are monitored to enable the secondary air injection monitor?

Thanks for the Help.

ColoradoDave · May 29, 2015

I understand what you are saying, however, does your scanner say you are ready for emission testing?

Williamsauls · June 1, 2015

No. My scanner shows secondary air not monitor not ready. I even paid to have the truck emissions tested with the hope they would pass it with one monitor not ready. It did not pass. I now know California requires all monitors to be ready. I recently tried resetting all monitors hopping this would fix the issue. No change, all monitors except secondary ran and passed on the first drive cycle. I'm still having the same issue.

BlackZ71Silverado · June 1, 2015

I hate to recommend going to a dealership but that may be your only option. They should be able to take care of that reset using a tech2. Unless you know someone who has one, dealership for a reset may be your only option.

Sent from my crappy iPhone 6

using Tapatalk

Williamsauls · June 2, 2015

I have heard that a tech 2 tool can set the monitor to ready. I would like figure this one out without manually setting the monitor. I can't go to the dealer every time I disconnect they battery. I would think there is some underlining cause for the monitor not run its tests. I'm going to try these items tonight

1) Disconnect the battery and ground out the positive cable.

2) Clean the mass air flow sensor.

Fingers crossed...

BlackZ71Silverado · June 2, 2015

I didn't suggest going to a dealer every time you disconnect the battery, you may of somehow misunderstood the post?

If you've been around here a while, you would know that I never recommend going to a dealership service department. I strongly support doing ones own maintenance and repairs if possible. I also believe in supporting smaller area shops but in this case, dealer service seems like your best option. A dealership with Tech2 capability can at least have it diagnosed properly, at least you will know what's wrong.

About the battery disconnect.......If you are having to disconnect the battery on a regular basis to reset check engine lights, clear codes, or reset sensors, you have much more to worry about than just an air monitor.

You don't have to have a dealership look at the truck to at least let you know what's going on, you can keep throwing money at it replacing parts and hope that it fixes itself, that's your decision.

I am just saying that with something like this, an off the shelf code reader isn't going to help much as you have experienced. A GM Tech2 would be extremely helpful but you don't like that idea for whatever reason......good luck with the repair of whatever is causing your issue.

If you can, keep everyone updated as to what the problem was and how it was fixed in case anybody else experiences this issue.

Sent from my crappy iPhone 6

using Tapatalk

Edited June 2, 2015 by BlackZ71Silverado

Chris · June 2, 2015

Well actually OP can pass. Under CA Smog test 1 monitor can be incomplete. If 2 or more are incomplete then it is a fail. Normally the one that people test incomplete is the Evap.

Mr Joshua · July 18, 2015

Evap monitor is the only monitor that is allowed to be down. As for the secondary air injection monitor, its being suspended because the ECM is seeing a problem with most likely the O2's even though they passed their own monitor. What you need to do is access your mode 6 data. it stores the pass/fail criteria. A monitor can be suspended if any one test is close enough to failing. If you have access to a snapon modis you can see the mode 6 data quite easily but its hard to decipher. This is where your local dealer can help if the drivability tech will show you the right monitor test ID numbers to look at. I'm currently having this very same problem with a GMC truck that i cant get through the smog test. This is a very tough problem to figure out even for a tech such as myself with limited information.

holdenoak · October 9, 2015

Thank you Joshua, was starting to think no one here had a clue. Black Silverado, think you are getting too excited. He only said he had his battery replaced and this happened, not that he disconnects regularly. Anyway, I have the same problem and all tests in Mode 6 are passing. Have a Tech 2 and I am GM certified and can not force the monitor to pass. Did anyone here, find a solution?

Mattt · October 27, 2015

Add one more 2001 Silverado with a 4.8 to the list of incomplete I/M Readiness tests, the Sec Air System as "inc." I've gone round and round with this truck since May and this problem. No matter what is done, the Sec Air System will not complete. The truck has 150k on the odo, runs great, no stored codes.

What is the definitive word....can you pass a CA Smog check in 2015 with one I/M showing incomplete? Can it be the Sec Air System showing Incomplete?

One more twist to my story....this truck does not have functioning A/C right now and has not for over a year. The A/C light on the controls lights up, the fan turns on, it just does not blow cold. I suspect a refrigerant leak, but have not had it checked.

I know some drive cycles say to have the A/C on during a particular procedure.....is there any way possible that lack of A/C working would prevent the ECM from trying the Sec Air System test? Seems unlikely, but figured I'd throw that in there.

I'm hoping someone before me has figured out the solution to this puzzle and would not mind sharing it. Thanks in advance.

Edited October 27, 2015 by Mattt

Williamsauls · October 28, 2015

So my truck finally ran the secondary air injection test and passed smog!

It's funny because I had just scheduled an appointment with a Californian Smog referee to see if they could help diagnosis the issue with the 2A injection. On the way to the appointment the 2A test ran. I've been trying different GM drive cycles for 2 months with no luck. I've drove my truck to work each day, 20 miles, and completed a the standard GM drive cycle with no luck. I guess what the truck needed was a longer drive. The drive to the Smog Referee was approx. 35mile. I guess what I'm trying to say is don't trust the standard GM drive Cycle. Sometime you just need to put some miles on the truck. I read somewhere that if the 2A injection fails it initial test or the test is marginal, then a more elaborate test is conducted. This elaborate test can require a longer drive to finish. This is why sometime the 2A monitor will set as soon as the car starts and other times a drive cycle is required.

Matt,

In California a The Smog laws have recently changed. You will not be able to pass Smog without completing the secondary air readiness. I would suggest taking the truck for a full drive cycle then putting on some highway miles. What's you normal driving routine? How may miles do you drive each day? If the truck has no codes, you should eventually pass the 2A monitor. I know driving more is not the answer that you want but after trying every option imaginable, driving more ultimately fix my issue.

Mattt · October 29, 2015

Williamsauls, Thank you for replying back. Would you say it ran the test due to one drive that was longer, more miles?.....Or would you say it was just the sheer number of miles you racked up on the odometer over time?

I found the info that no I/M monitors can be incomplete now...and that is really stupid and short sighted if you ask me. Now my truck will NOT be smog checked for who knows how many months until this test runs. It's already been since May. This ridiculous rule put in place by unelected Jack booted thugs who are living high off the hog of CA Taxpayers, CARB(California Air Resources Board), courtesy of one party screwed up rule in this formerly great state...but I digress.

I guess I'll just keep driving and hope it runs the test at some point. Thanks again.

Mattt · December 4, 2015

Moving this back up in hopes someone has a solution. I have driven my truck many hundred miles, probably thousands of miles and still Sec Air System is INC. As an example, yesterday I drove 100 miles in mixed traffic in the city. My driving ranged from 70mph full speed freeway to bumper to bumper traffic, street driving typical, idling, stop and start at least 5 times. Still INC....this has been going on since May and still will not clear that test. I've disconnected the battery and all other tests run and clear...except Sec Air System.

Help!

Thanks in advance.

2000CHEVYBEATER · January 25, 2016

Hello Everyone

I just joined to share my recent experience with a 2000 Silverado. Everything is related to this thread and some of my actions where guided by info on this thread.

So the truck sat unused for a long time and the battery went dead, beyond recovery. Installed new battery and took to get smogged in N. California on December 22nd 2015 - truck would not pass because "OBDII MONITORS NOT READY". The tech gave me a print out of the required drive cycles and I left and then performed them several times. I brought the truck in and all had reset except "Secondary Air System" Between December 22nd and Jan 21st 2016 I brought the truck back to the smog station 4 times and drove a total of 1300 miles - but Secondary Air System always showed not ready.

January 21 I gave up and brought the truck to a chevy dealership who had a Chevy certified "Master Tech" on staff who had worked on several other chevys with same problem. I passed on info from this site regarding using the Tech II tool to reset the sensor.

So day one he checked the computer which was working fine and did not need any update. He noticed the engine temp reads would not go below 82 deg F even after the truck sat idle for 4 hrs so he thought maybe a sensor need to be replaced but could not be sure until he let the truck sit overnight to give it a chance to completely cool down...

Day two, engine temp read out was 51 deg F. Tech took it for a test drive and notice the engine temp never went over 160 deg F. The tech stated the trucks computer would not run the Secondary Air diagnostic until the engine temp reached operating temp over 200 deg F. He pulled out the old thermostat which was working but was out of spec for this application and put in a new thermostat with correct operating range - test drove again and returned to shop and hooked up to monitor - all Monitors showed ready!! On Monday Jan 25th the truck passed CA smog.

So in summary : an out of spec thermostat that some idiot put in cost $770.00 in diagnostic/repair charges. (could have been worse because I took out a rental car from the dealership, but they didn't charge me) and a full month of frustration and gas money since the truck is not really a daily driver but more of a Home Depot weekend truck..anyway

Hope this info will save somebody the frustration.......check your thermostat!!!

Mattt · February 15, 2016

Months later.....Secondary Air system still has not run and gone to OK in I/M readiness. I checked the engine operating temp and it runs just above ~200*, 203, 205. One thing I did notice when viewing Live Data with engine running is that Secondary Air system result shows "Atmos." I'm not sure what that is telling me, but would like to know.