If you want to just test your SAS valve then bypass the switch. You should be getting a constant vacuum.

Or better yet you can activate the switch by supply it with some external 12 VDC.

 

Where is the switch at? Are you talking about the small air pump behind the engine? The device where the check valve vacuum hose is coming from?

 

You have a 2001, if the vacuum hose from the Kombi value in the front of the engine has not been replaced, it needs it. The hard plastic line along the valve cover cracks and breaks after about 7 years.

I rarely see the SAP vacuum control valve under the intake have problems.

You could also just put a vacuum gauge on the connection for the Kombi valve and see if you have vacuum when the car is started and the SAP is running.

 

There is nothing wrong with the SAP or check valve, the vacuum hose to the check valve did indeed crack and I replaced part of the line (using new hose, a vacuum coupler, and silicone adhesive). I could not check earlier however if there was enough vacuum to open the check valve because the secondary air system wouldn't come on (I already ran the car, engine not cold enough I'm assuming).

I know the legit way is to replace the entire vacuum hose, but I don't know how to get behind my engine to where the hose goes to.

 

You can activate the secondary air pump with INPA.

 

...and you can get to the hose behind by removing the cabin air filter housing...then if you need more room, remove the panel this housing screws into. T-40 screws iirc

 

I guess my question is why do you need to do this?

You will get a DTC & CEL if you have a problem with the SAP system pretty quickly and/or the SAP Emission Readiness Monitor will not clear if you reset the codes.

BUT, also note that the O2 sensors play a role in detecting if the SAP system is functioning properly, so you need to be careful how you troubleshoot the system.

Do you have a problem with the SAP system?

 

Well I know 100% sure that a problem with the secondary air system will not trip the CEL light because yesterday is when I discover the vacuum hose to the secondary air check valve was broken so it remained stuck closed.

The only reason I'm trouble shooting this is because I have no CEL and my secondary air smog monitor won't clear (I've posted a thread on this previously).

So basically i'm in the middle of trouble shooting. I fixed the vacuum line going to the check valve and I verified this morning that the valve DOES open properly now when the secondary air system is running. And yes the pump works too.

So now I just need to see if the secondary air monitor will clear. How many cold starts does it take to clear the monitor (assuming everything else is working fine)?

Edit: My smog thread here: http://forum.e46fanatics.com/showthread.php?t=1014226

 

And, the SAP will most certainly trigger the check engine light. Don't hold me to the code, but I think it something like P1423.

 

In my case, a closed check valve did not throw a code (and YES my check engine light works!)

 

You can blow into the engine :dunno:

 

Here is the problem, there is not a lot of solid info out there about how many drive cycles it takes to either trigger or clear a DTC or an Emission Readiness Monitor.

What I can tell you is if the Readiness Monitor for an item does not clear, you may never see a CEL for it, or it may be like 40-60 drive cycles?

If the SAP system and O2 sensor are working properly, the SAP will usually clear in the first cold start cycle. I find the SAP is usually the first and easiest Monitor to clear.

An option is to clear the codes again, even if there are none, this will set all the Emission Readiness Monitors to Not Ready, then see if you can get the SAP to clear on the first cold start in the morning.

If the SAP does not clear easily, then you may have a questionable O2 sensor.

Graphing the O2 sensor is the best solution as you will be able to see exactly how well the SAP system works based upon the O2 sensor signature.

You can have a lazy O2 sensor that will not trigger any codes and also hold the SAP Readiness Monitor from clearing quickly.

Read this thread if you want to know what kind of ride you may have ahead!

http://forum.e46fanatics.com/showthread.php?t=954362

 

Only 1 cold start and it should clear? Well I'll reset the codes tomorrow morning with the engine on but not started, then start the car. I'll let it idle for about 10 minutes and check if the SAP is cleared.

If it is not cleared, then you agree the next troubleshooting step is to graph the O2 sensors?

 

SAP should clear in the first 90-120 seconds if it is going to clear. Wait no more that 2 minutes before driving, as this will speed up the O2 sensor activity and the car should be in closed look within the first 2-3 minutes under most circumstances.

Just note that since I did not write the DME software, I do not know ALL the ins and outs of the logic. I do know that sometimes if there is a code or maybe the Emission Readiness Monitor has not cleared, there may be a routine that requires a certain number of cold starts before the code or Monitor clears as the system was used to a problem and now it wants to make sure the problem is really resolved before moving on.

If you have the ability to graph the O2 sensors, this will pretty much answer most of the questions.

This is why the OBDII tools that graph Live/Real Time sensor data are so useful.

I can look at a graph for O2 sensors for 2-4 minutes and I can see the SAP running, the O2 sensors warming up, the SAP shutting off and the sensor activity.

 

Ok after a cold start this morning I still see the secondary air monitor not clearing.

Now I'm going to get the scanner I need to plot the o2 sensors.

jfoj, can you link me the tools I need to order please?

 

3 low cost options for probably under $35 each.

http://forum.e46fanatics.com/showthread.php?t=967204

Readers digest version, smart phone App and an Interface, PAY CAREFUL attention to the type of interface that is required.

Andorid Apps: Torque Pro, Touch Scan Dash Command and a Bluetooth to OBD adapter like the ELM327.
iProducts: OBD Fusion and a WiFi to OBD adapter.
Windows laptop: OBDWiz

4 minutes cold start idle will pretty much show what is going on.

Again, SAP Readiness may take some time to clear if it was not working for a period of time as the DME may want to see more good tests, but if you have a lazy O2 sensor it will hold things up and you could have no code for SAP or an O2 sensor.