Hello everyone.
I recently rebuilt my alternator and replaced the electrical cables. The good news is that my battery and electrical systems seems much happier now.

The bad news is that my '99 996 cabrio is throwing codes P0410 and P1411.
My SAI is coming on as expected (like a vacuum cleaner really).

I think I may have messed up a vacuum line when I put it all back together. In particular there were two lines on the rubber bellows between the throttle body and the intake. These seemed very delicate (these are of the thin, hard plastic ilk) and I'm afraid they either were pinched or even fell out when I put things back together. Does anyone happen to know if one of these goes to the SAI system ?

In particular, does one of them go to #7 in the below diagram?


Thanks in advance. I hope this is somewhat clear.
Im looking at having to remove the alternator again, or maybe I only need to take out the throttle body (again).

I doubt any of the parts of the SAI system are broken. They were working (no codes thrown) before I took out the alternator, although maybe I managed to break something.

 

OZ951 may have answered my question. Thanks OZ! If the vacuum line in yellow in the below pic was disconnected or pinched would this cause a code to be thrown?

 

Super cheap way to troubleshoot, if you suspect those hard plastic vacuum lines are the culprit, just get similarly sized vacuum tubing from the auto parts store and replace it. Take it from someone that had an 951 with about one mile of that crap, they eventually get old, brittle, and crack in a subtle way that you won't be able to see.

 

Sjg, if the yellow line is disconnected, you will have a vacuum leak plus your SAI will not work because #2, which is powered by vacuum, will not open. However, I'm not sure those photos depict anything SAI related though.

Again, this link should help http://www.renntech.org/forums/topic...l-p0410-p1411/

I suspect you knock off the line between #2 and #3. Of course you should also check if #7 is connected to the intake.

 

Good to know OWP. The thing is, at the throttle plenum rubber boot, the hard plastic vacuum line is pressed through a small hole in the boot. I'm not sure how I could replace it with soft vacuum tubing, unless I used some sort of fitting (maybe metal) to go through the same hole.

 

You could use a barbed plastic or brass fitting, they should have them at auto parts stores or the local home improvement store. I redid my entire 951 vacuum system in black silicone (no bling!) and brass fittings. I'm paranoid so I used zip ties at the connections. Wherever that damn thing is today, it shouldn't have any vacuum leaks!

 

You can get the stock (hard) vacuum tube from the dealer. Sold by number of feet. Not too expensive like a couple of dollars per foot from Sunset.

Edit: checked my invoice, $4 per meter p/n G00004320501

 

Thanks Ahsai. To be clear, those photos are Not from my car. I just the photos to figure out how things are connected. If I do replace the vacuum hoses, I may do them in a color other than black, just so I can see them better.

 

Yea, I recognize those photos from OZ951's website i think his car is RHD so probably his car doesn't even have the SAI system, which is a US thing.

 

Which actually brings up another question - if you don't have emissions testing, could you delete the SAI system?

 

Unfortunately I'm here in California where we definitely have emissions testing. In fact, if the testing facilities detects any changes to the emissions system they can fail the car - Even if the car passes the emissions measurement test! This happened to me with a Mini that has a CAI installed. It passed the emissions measurement test but they failed it anyway (because of the mod).

I could really use a diagram of the vacuum lines if anyone happens to know where I can find it...

 

I remember replacing the entire 944 vacuum system with blue silicone lines from pelican parts or paragon products... Much easier to work with than the hard lines.

If you have a durametric, or a friend with one, you can manually run the SAI pump from the durametric to help troubleshoot. You should also be able to log the vacuum level while you do this, too.

 

So instead of taking everything apart again, I cleaned the MAF sensor and reset the CEL. I have started and driven the car three times with no codes thrown yet. Crossing my fingers.

I looked around with a mirror and cant see any vacuum hose issues. Everything seems to be back in place. Is there a chance that my rebuilding of the Alternator caused a problem? I have no idea if there is some sort of calibration build into to the SAI system. I know that it uses an oxygen sensor as an input. Does it use the MAF sensor as an input as well?

 

SAI code will take a good 100 miles before it comes back. sorry.