Ok I need help. I got a CEL for the secondary air intake system with the following codes:
P0491 secondary air system bank 1
P0492 secondary air system bank 2
P0300 misfiring checksum error
P0301 misfiring cylinder

I have a durametric which I reset the codes with and a few days later they came back. When I try to activate the air pump with the durametric I can hear the relay click (sounds to be on the drivers side above the rear wheel area) but the pump does not come on. For the life of me I cannot locate the pump. I spent about a 1/2 hour in the engine bay and under both wheels trying to locate it with a flashlight and no go. Where the hell is it. I have the diagrams showing the system so I know what it looks like but seriously need help in the actual finding part.

 

On the 996 is was behind the alternator. Might be able to get a small mechanics mirror back there to check. I looked at the 997 work book removal instructions which shows the pump but it is very hard to determine exactly where it is on the engine. Pic shows a knock sensor to the left and below the air pump and a wiring harness that looks very much like the alternator-to-starter harness with a plastic channel that is held on by a nut near the left side of the pump.

The link below is for the 996 air injector valve removal process but doesn't really show the pump itself.
http://p-car.com/996/diy/sai/mainpage.html

 

Thanks. I tried looking there but didn't have a mirror. Anyway I caved it's going to the local Indy in the morning.

 

Well while you're there have 'em show you where it is so you can post it up here. Then, anyone doing a search would be able to get an answer to the question. As these posts tend to stay here forever, the likelyhood of someone having the same issue you had increases as our cars get older and this part wears out.

 

Good point. I will.

 

In follow up Dadio, it's located in the engine bay right behind the rear seats. Definitely not a DIY unless you have the means to drop the engine at home. I'm handy, but not that handy.

 

Leave it to Porsche to find an inconvenient place for it.

 

Did they really have to drop the engine for this or is it something that could be accessed by removing the rear under panels?

 

Partial drop, remove half of the intake manifold. All in about 11 hours including 1.5 on diagnostics.