1997 850: throws DTC P0410 between 87-90 miles of drive Topic is solved

Post by **erikv11** » 26 Apr 2019, 14:57

OK good to know, I was just just guessing about why there may be two different exhaust manifolds.

Post by **misha** » 26 Apr 2019, 14:58

Turbo and n/a manifolds?
Document shows Volvo sas system....it's the same on late 850s and s,v,c70....it's not specific to 850 only.

Post by **erikv11** » 26 Apr 2019, 16:13

misha wrote: 26 Apr 2019, 14:58 Turbo and n/a manifolds? ...

Oh of course!

I've never had a turbo with SAS so I didn't think about it, but on a turbo car the SAS valve mounts into the downpipe (use pipe #34) not on the exhaust manifold. There is no SAS bung in a turbo exhaust manifold. For an NA the SAS valve mounts into the end of the exhaust manifold (pipe #11). I think there are even NA manifolds with the bung further down, as well.

Turbo car setup:

: 025.jpg (130.16 KiB) Viewed 1905 times

and this

: sas_pipe.jpg (45.23 KiB) Viewed 1901 times

Post by **abscate** » 26 Apr 2019, 16:32

DOHC is Swedish for no SAS, or is that the airline?

The “ dual valve “ picture above is a bit confusing, but Volvo diagrams will show different versions of a system on one page, so that one gets confused.

Post by **misha** » 26 Apr 2019, 16:36

erikv11 wrote: 26 Apr 2019, 16:13
misha wrote: 26 Apr 2019, 14:58 Turbo and n/a manifolds? ...
Oh of course!

I've never had a turbo with SAS so I didn't think about it, but on a turbo car the SAS valve mounts into the downpipe (use pipe #34) not on the exhaust manifold. There is no SAS bung in a turbo exhaust manifold. For an NA the SAS valve mounts into the end of the exhaust manifold (pipe #11). I think there are even NA manifolds with the bung further down, as well.

Turbo car setup: 025.jpg

and thissas_pipe.jpg

Case closed!

Post by **xHeart** » 27 Apr 2019, 11:31

Ours is fitted with SAS for naturally aspirated aka non-turbo. The air pump is situated under the battery tray, but accessible with air guide off.
It is idling closer to 1000RPM -- you can feel her anxiety.

We are in our 5th winter this year.

Post by **misha** » 27 Apr 2019, 12:20

N/a with automatic transmission is idling close to 1000rpm when it's in "D".
Manual a bit less.

Post by **xHeart** » 28 Apr 2019, 11:36

misha wrote: 27 Apr 2019, 12:20 N/a with automatic transmission is idling close to 1000rpm when it's in "D".

Correct, but I'm used to it idling close to 850rpm in "P" with engine warm.

Should I just go ahead and service the valve -- hose connections for damage, repair, and replace gasket?
Here is the setup:

: MVS_Sas_0078.jpg (204.36 KiB) Viewed 1659 times

Post by **misha** » 28 Apr 2019, 13:11

Sas valve is not serviceable.
Internal diaphragm is usually burnt over and because of that it gets stuck open.
If it's allready stuck open...air pump is on it's way out too since all condensation from exhaust manifold ends up via bad sas valve into the pump....after that on wot ends up in the air filter messing up Maf sensor.

I got 2 maf sensor failure due to this problem untill i realized where from all that water(condensation) ends up into air filter.

Sas delete is my advice ...since it's useless.

Post by **xHeart** » 29 Apr 2019, 11:58

Robert's DIY video

[youtube][/youtube]