hahnmgh63

This was posted in a thread a while back and I asked the guy who posted but never got back to me. I just finished replacing the Coolant Tee's ('06CTTS) and I pulled both SAI pumps off and removed the brackets and have now run the Pig for at least 300miles and I get no SAI fault codes. Kind of surprised me as my Audi RS6 also uses a Bosch 7.1.1 Motronic and it will give faults without custom software if you remove or disable the SAI system.
Now I'm throwing this out there for FYI, please any Greeners lay off on the comments. Really, the SAI system is a bunch of junk the manufacturers had to come up with to win at the first 1 to 2 minutes of the EPA cold start driving cycle. Yes, for all of that equipment, it only runs for the first 1 to 2 minutes of a cold start. You can easily past a tailpipe emissions test without it since your vehicle is warm by the time you get there. Only if your state or area has a visual inspection and they know what to look for would you fail. Just FYI
P.S. I didn't remove the SAI injection valves at the back of the motor as they were too much of a pain to get at and I wanted to get some miles on it first to confirm there were no faults.

ericstaup

So could you explain the proceedure a bit? Just plugged the hoses after removing the pump?
Thx...I have been Running with a secondary pump failure code for a coup,e years now and would like to do something about the code other than buying a new pump if possible.
Eric

spooltime

How did you close off the plumbing to the pumps?

Dilberto

From experience with my Audi allroad 2.7TT - the SAI can be removed and block-off plates used at the Kombi valves, to terminate flow from SAI. The Audi 2.7TT will throw a CEL code, which must be coded-out, via VAG-COM. I believe the Porsche system is similar....

hahnmgh63

The Audi 2.7tt is close but slightly different. It is Motronic 7.1 whereas the 955 Cayenne's are 7.1.1 (same as the RS6 which uses the exact same SAI valves, therefore the same block off plates as 2.7tt).
For now all I did was unplug (tie wrapped the plugs to the harness behind so they wouldn't flop around) the SAI electric pumps and removed them and the brackets (3 bolts, need 12point 10mm socket) and I used some plugs from Napa in the hoses to plug them with a clamp for a tight seal although the SAI valves are a one-way valve so you are really just keeping dust out of them. I will later remove the valves after a few hundred more miles just want to get a couple more driving cycles to be sure. As Dilberto mentioned the Audi's will throw a SAI code just by unplugging the pump (single larger pump on the Audi's). ericstaup, what SAI code are you getting? Have you tried to just clear the code, unplug your pump, then restart and run it? I'm curious too. Like I said this is on a '06 CTTS so I would think as a minimum all 955 Turbos would be the same but any 4.5 I would think would be the same. I think to remove the valves it will have to be done from beneath but you could always just leave them in case you sell in a couple of years and the buyer lives in a visual inspection state. Then just unplug the hoses, re-install the electric pumps and plug them in.

bigbuzuki

What is the weight saving gained by removing the equipment?

hahnmgh63

Not much of a weight savings when your talking about a 5000+lb vehicle but it clears up the back a little and makes it easier to get to the plastic Coil pack covers off as well as making it easier to get to and inspect any of the vacuum lines and hoses at the back of the engine.

J'sWorld

Your probably going to get 2 codes. P0491,& P0492. Sometimes it takes awhile. If you hook up an obd code reader it will show the readiness monitors for that as not ready. After some key cycles and requests from the ecu it will activate the fault light. Something else to ponder, on cold startup when its running real rich, that air injection provides oxygen to unburnt fuel in the exhaust. Long term, cats dont like being exposed to overly rich mixtures or raw fuel.

ericstaup

I don't remember the codes but they were for a secondary pump failure...I had the code cleared 3 times and always came back. I do smell a rich mixture of fuel when first starting at idle. Maybe I should re think this as I really don't want to toast the cat converters. It has been about 50,000 miles without issue so far though.
Thanks
Eric

user 83838290

Good to know.
Just 2 days ago, I started the car while scraping off ice & snow and I could hear the secondary air pumps turning off after about 2 minutes, maybe even less (and it was cold, -15 C / 5 F).
Per my AFR sensors, my cats get blasted with richer mixture at WOT anyways, so I'll just remove the pumps as well when I'm back replacing wastegates and get them coded out.

hahnmgh63

I only have a few hundred miles so far with no codes and yes, I am surprised. As I mentioned, my Audi RS6 (twin turbo V8) also has the same Motronic version (7.1.1) and it will give codes if you disconnect (I did remove the SAI system when I went Milltek Catless but I had to get custom software to code out the SAI and secondary O2). I'll continue to drive it and will report back if anything pops up. I just scanned it the other day and there isn't even a hidden code yet as I know the codes will show up hidden if there isn't enough repetitions to set off the CEL but so far so good.

csm diesel

Do you have an update to this? Any codes?

jpru2001

this. I have a dead one and only get the P0492 once every few weeks. its coming.

J'sWorld

hahnmgh63

I did get the P0491 & P0492 codes every couple of days. It would take 2~4 complete warm up cool down cycles to appear and then it would set off the DTC/CEL. Since I already am running a Eurocharged Tune I contacted them and they uploaded a custom tune for me that coded out the SAI system so no more codes or DTC/CEL for me.