OK - I'm bringing this thread back from the dead to add a few more useful bits of information to it after going through practically HELL to get this thing fixed on a 98 VR.
First of all - There are 3 components to the SAIS -
1) Secondary Air Inejction Pump - Expensive
2) Secondary Air Injection Valve aka Combi Valve aka Kombi Valve aka EGR Valve - Approx 200$ from http://www.worldimpex.com
( http://www.worldimpex.com/item...39722 )
I have part numbers for 2 and 3 for a 98 VR I can post Later.
While you have the car torn apart to the state shown in benny_mech's first pic I woud recommend getting at least 2 feet of vac tubing and replacing all the vac-tubing in this system. In my car there was a U shaped section that ran from the Intake to the Fuel Pressure Regulator that had a T fitting in the middle of this. Off the bottom of the T fitting was a line that went down to the solenoid, and a second line that came off of the solenoid that went to the Kombi Valve.
Bold for Emphasis On a 98 VR every last INCH of that vac tubing was crumbling in my finger tips. Do yourself a favor and replace ALL of it .
Secondly - Here's some helpful troubleshooting info...
This is a picture of the Kombi Valve. The black part connects to a plastic tube that connects to the actual Pump. The Left hand side shown in this picture attaches to a metal piece with an O-ring that inserts into your motor. The vac nipple (bottom right) should have Vac tubing attached to it.
To determine if you valve is bad remove it from the motor completely. Put your lips around the black section and blow. If air passes through the valve it is bad. Now find a source of vacuum (power brake bleeder, or temporarily steal the line coming off the bottom of that T fitting and have a buddy start the motor briefly). Put vacuum onto that nipple. With vacuum applied you should be able to blow through the Kombi valve with a minimum of difficulty. If you can blow through the valve with NO vac, or you cannot blow through the valve WITH vac then you probably have a bad valve. Prepare to spend 200+ $.
In my case all the vac tubing was basically destroyed. I opened up the motor, replaced it all, put it back together assuming that would fix it, and boom. Same code. I did not know how to check the valve at that point, so I did not think to check it.
I then had to open up the motor again, and check the valve. Turns out the valve was OK. replace the 11$ solenoid and boom! I was in business.
I dont have a good procedure for testing the pump if you do not have a vag-com. With VAG-COM Start the motor to idle. Open Controller, Engine. Open Basic-Settings. Block 160 will test the SAIS. Have a buddy stand by the front of the car. He/She shold be able to hear the SAIS Pump turn on for a short time and pump air. If what you hear sounds like a shop-vac your valve is staying closed. This could be because of a bad solenoid or a bad valve. This should be audible inside the car at idle (even with a loud exhaust). . I dont know what the other conditions will sound like.... this was the only condition my car experienced.
Edit: Last but not least - if you're dead-set on checking the 11$ solenoid before replacing it... let the car get cold. By the time you get it this far taken apart it should be more than sufficiently cold. Put the vac tubing that goes from the T fitting to solenoid in the right place. Attach a length of vac tubing to the solenoid on the nipple that should lead to the combi valve. Hold your thumb over the piece of vac tubing that should go to the Kombi valve and have a buddy start the car briefly (15-20 seconds). You should be able to feel vac on your thumb. If you cannot, disconnect the other piece of vac tubing and check for vac on the tubing coming from the T fitting. If there is vac on the T fitting, but none on the solenoid on cold start then your solenoid is malfunctioning.
Modified by Xanthazar at 10:21 PM 9-9-2005