FIXED - 2010 Impala p0411

I can intermittently force the air pump, relay, and solonoid on, but can't figure out why they are quitting. The relay tests fine everytime I put the power probe on it, but through the scan tool not everytime.

I'm not very familiar with electronically controlled diverter valves. It has five pins and a few appear to be reference voltage for something.

One time I forced the motor on and about 5 seconds in, it turned itself off. When it doesn't work, it takes a minute to start working again, like a thermal issue.

I'm guessing it's either a command issue or a failure at the beginning of the circuit.

I'm guessing it's the diverter valve but am worried about this intermittent operation of the system in general.

are you getting power/ground to the air pump when it doesnt work? could just be a failing air pump. id back probe or pierce the wires but seal them up when done

I'll check that. Thanks. I was thinking today that the pump sounded loud. I'm not sure what it should sound like buying was thinking that the air from it would have to be strong enough to push past the valve, again engine vacuum, right? This theory would explain why the air direction would be wrong.

It sounds like a harrier jet taking off. I'll YouTube a properly functioning one.

sounds like the diverter valve is stuck closed if its that loud.

How can I test that without pulling it off and running the system to see if the valve opens?

what engine is it?

The 3500.

you should be able to see the oxygen sensors go lean when you turn the air pump on if the diverter valve is opening up. if you dont the valve isnt opening.

Ahh! Of course. Thanks!

Ok, the O2 sensor did lean out. Here is more information. I notice that when I pull I have another Impala here and I noticed that when I pull the hose off of the intake boot from the pump and activate the solonoid relay, it clicks, but nothing happens in terms of air flow in the tube. I did this on another Impala and found that exhaust came through the tube, unless I turn on the air relay too, then it sucks and forces against that exhaust gas.

This makes me think the valve isn't opening, but why did the O2 lean out? I was expecting stft to correct that but it didn't.

Last bit if info is that the pid for airflow calculated under AIR functions went from 0 to 500 g/s then repeated, steadily climbing on this car and my test carit stayed constant at like 2.3 g/s. Is that the MAF or something that's part of the valve?

Now I don't know if I'm getting closer or just confusing myself!

I feel like the test car I used shouldn't have had any exhaust coming through the valve. I thought there was a check valve there to make sure that doesn't happen. That car had no codes for this but I feel like it was not a good test car to use to help out!

The car I'm working on, I saw the O2 lean out for sure, down to 60mv whole the pump was running, but, why didn't the stft correct that? Could it be that the ltft had already reset to this as a baseline during pump operation and so the stft stayed near 0? Seems unlikely.

Ok, last time ill list about this. The pressure voltage is the same with just the pump on and with the valve on with the pump when it is supposed to be less with both on. I do hear some air flowing through the exhaust but it's very faint. Im thinking the valve is opening but the pump isnt pushing enough air.

Thoughts?

<sup>It was the valve. I ended up taking it off and dismantling it. I imagine at one point there was some sort of rubber diaphragm in there but it was all in pieces. With it removed from the car I plugged it in and it was doing nothing when I activated it's relay. The new one made a distinct plunger sort of sound.

Im still not sure what to make of why the O2 went lean when I activated the system. I guess I just don't know know exactly how that part works, even after having it all apart. I'll post a pic to show the inside.</sup>