Hello Rickf,

Don't know if this'll help you or not. I've never really messed with this system on the volvo. I did however have a simular problem on a VW rabbit years ago.

In my case a small portion of the injector hose had broken loose and lodged in the fitting. If I remember correctly (certainly not a pro on the matter), Volvo used hard lines though. Worth a check maybe, dunno.

I'd go for the pattern / flow method shown earlier. (which is what we did)

After a couple weeks of the car sitting while I tried to come up with ideas, I decided to just trace the system back to the cause of low flow. When I removed the injector hoses to try the flow test through just the hoses (no injectors), the culprit dislodged and suddenly they were all flowing the same. Put the hoses back on and it ran like a champ. Yanked a JY hose and replaced the one I had trouble with. Drove the car 2 more years b4 getting too annoyed with the car's lack of a trunk and the ride. Sold it to my brother who's still driving it 2 transmissions and 12 yrs later with the same junk yard hose.

Like I said, I have NO idea if this will help you, but perhaps.

Best of luck,
Frank