troubleshoot help and parts question

[BoydCrowder]

04 XC90 with t6. Thing would cut off occasionally when slowing down. Had a cracked vacuum hose. Replaced it and car idles much smoother, but then would abruptly cut off when taking foot off gas (like coasting or hitting brakes). Did it many times in short distance after replacing hose - sometimes coasting down hill at 40 miles per hour!

Was getting code for too lean bank one, bank two. Light went off after fixing vacuum hose by the way

So I unplugged the battery to reset and drove with no problem. Now it cut off again once since then just once while braking.

Any experience on this sort of thing? Fuel pump relay, Fuel pressure sensor, camshaft position sensor?

Someone said this one doesn't have a fuel pressure sensor, but Auto Zone and Rock Auto sure sell one.

Any advice greatly appreciated

[wanderdüne]

No, there is no fuel pressure sensor, rather a fuel pump control module #30742823. I cannot speak to the symptoms on the module, but there are plenty of threads on the forums about issues with that. I suggest that you change out the fuel filter first thing. Because why not, it's inexpensive, and good to rule out as a baseline.
In terms of sourcing parts, I suggest you go with OEM parts from sources like FCPeuro, iPD, RMeuropean, or Tasca and LIsle Volvo for dealer parts. These are all trusted and knowledgeable sources with good pricing.

[SuperHerman]

Have you looked at the MAF? Also there is another valve - don't recall what it is called - by the Driver side strut tower (not the turbo valve). I had a similar problem and it was one of those two - but it was throwing a code.