Secondary Air Pump

[osamabatrikhi]

Hi,

 

I have the following codes on my cayenne V6, P0491 & P0492 (Secondary air injection System insufficient flow bank 1 & 2 ), I have checked the Pips ,the relay and the fuse, all are OK, the pump has no sound unless when I touch it i feel something like rattle.

 

should i replace the pump?  

what are the symptoms and impacts of bad secondary air pump? does affect the performance of the car?

 

 

 

[JFP in PA]

You should first scan the car with a Porsche specific scan tool (Durametric, PIWIS), which can start the SAI pump without the car running.  If it does not run, I would check the electrical connections to the pump, and attempt to run it on the bench before replacing it.  Sometimes these pumps get gummed up internally and a simple clean out gets them back up and running.

[osamabatrikhi]

does the SAI pump affect the performance of the car?

Edited October 19, 2017 by osamabatrikhi
missing word

[JFP in PA]

No, it is an emissions control device.

[osamabatrikhi]

Thanks, I appreciate your response

[ekstroemtj]

On 19.10.2017 at 11:38 PM, JFP in PA said:

No, it is an emissions control device.

 

@JFP in PA greetings to the specialist. 

 

What will happen exactly if the valve connected behind the pump is not working? 

Friday i start to hear a noise which is almost the same like a leak in the exhaust. Found out it’s coming the secondary air pump or the valve.  The pump is still working but sounds different than the passenger side.  Disconnect the black big hose which is routing to the valve I can hear air and feel something like exhaust gases. Valve  smashed?

[JFP in PA]

1 hour ago, ekstroemtj said:

 

@JFP in PA greetings to the specialist. 

 

What will happen exactly if the valve connected behind the pump is not working? 

Friday i start to hear a noise which is almost the same like a leak in the exhaust. Found out it’s coming the secondary air pump or the valve.  The pump is still working but sounds different than the passenger side.  Disconnect the black big hose which is routing to the valve I can hear air and feel something like exhaust gases. Valve  smashed?

 

The vehicle will code because the pump is in effective.  Usually the valve sticks due to build up, but they can fail electrically as well.

[lewisweller]

3 hours ago, ekstroemtj said:

 

@JFP in PA greetings to the specialist. 

 

What will happen exactly if the valve connected behind the pump is not working? 

Friday i start to hear a noise which is almost the same like a leak in the exhaust. Found out it’s coming the secondary air pump or the valve.  The pump is still working but sounds different than the passenger side.  Disconnect the black big hose which is routing to the valve I can hear air and feel something like exhaust gases. Valve  smashed?

Thomas I had the same issue the valve is stuck open and allows hot exhaust to pump back into the pipe and into the air pump. 

Use a 1/2-3/4" GI plug can't remember the exact size (Pic attached)and jubilee clip to close the pipe and forget about it. 

Pulsing sound will be gone as well. 

 

The valve part no 10 is not electronic, its mechanical only, it's spring loaded and the air pump opens the valve against the spring pressure. You can replace the valve but it is extremely difficult to access. 

 

[ekstroemtj]

Thank you guys.  As I understand you well Lewis,  the Valve is stuck open. Reason can be mechanical because the valve is defective or the pump is not strong enough anymore to open /  close the valve?

thank you very much

[lewisweller]

25 minutes ago, ekstroemtj said:

Thank you guys.  As I understand you well Lewis,  the Valve is stuck open. Reason can be mechanical because the valve is defective or the pump is not strong enough anymore to open /  close the valve?

thank you very much

Block it off and forget about it. 

[ekstroemtj]

3 hours ago, lewisweller said:

Block it off and forget about it. 

 

Just afraid it will influence Lambda reading or my emission Test which I have to pass

[lewisweller]

1 hour ago, ekstroemtj said:

 

Just afraid it will influence Lambda reading or my emission Test which I have to pass

It won't do either. 

It only operates  the first 20sexond of a cold start . After that it's completely unused. 

[ekstroemtj]

4 hours ago, lewisweller said:

It won't do either. 

It only operates  the first 20sexond of a cold start . After that it's completely unused. 

Great! Thank you Lewis