Can't find the vacuum lines (diagram or actual) for SI6 engine V6 2007 XC90 model

GreenMagicMan · Post by **GreenMagicMan** » 04 Sep 2020, 08:43

Hello fine forum people.

We have a 'loping' often surging / cycling sound on idle on the engine of a 160K miles SI6 (V6) 2007 XC90.
I read around that it is likely or first place to look anyway a vacuum leak.

Both our V6 cars have a diagram under the hood. But it basically just shows a single line in front of the engine under the intake. I've looked and can't find even that line in the engine.

Not sure about other lines to check.

Post by **BEJinFbk** » 04 Sep 2020, 13:45

You'll get better results posting in the right section for your XC90:
viewforum.php?f=10

Post by **ggleavitt** » 06 Sep 2020, 14:45

See if you can find what you're looking for in any of the diagrams. All the Volvo resellers have the same portal, this is an example- https://parts.volvocarslisle.com/Volvo_ ... ngine.html

chitownV · Post by **chitownV** » 06 Sep 2020, 17:33

What maintenance has been done to the engine over the years? Have you changed the PCV valve yet? If you pull the dipstick or open the oil filler cap while the engine is running, can you hear air rushing in?

GreenMagicMan · Post by **GreenMagicMan** » 08 Sep 2020, 12:57

I read this link, thank you. I am guessing there are many more vacuum lines than shown there. I can't seem to find a solid diagram for it all.
Looking at my notes from July, this V6 2007 was throwing CEL codes:
174 system too lean Bank 1
455 eval sys leak large

Flashing CEL the other day, and eventually driver told me they 'smelled something like hot glue / burning' and that the steering wheel was 'smoking' and pulled over finally and it was towed back to the home and has sat for 3 days.

PCV valve is unknown if / when changed. I will do a suction test on the oil filler cap today.
Unknown maintenance was a auction buy.