Unfortunately I see it almost everyday, I like to call it "fear of the unknown".
We have 125 2012 Volvo's with 13L engines and no cartridge for the scan tool(125 out of about 9000 truck none based at my location it'll be a long time before we see a cartridge), so one shows up with 40,000 miles and a no power complaint, 2 mechanics shaking their heads we don't have a cartridge they tell me.........Is the check engine light on? ...........no ........well you've got a couple choices use the fuel pressure test gauge we used for the last 30 years before electronic engines and check the fuel pressure, visually look at the glass dome on the primary fuel filter to see if the fuel level is up the change filter line, or just change the $3 filter and take it for a ride...............$3 and 5 minutes later the truck runs good again but the head scratching and no cartridge discussion took 45 minutes.
Bottom line it's still all about the basics, knowing the PM schedule is 3 months or 45,000 miles and the truck had 40,000 on it, no power complaints without a fault light, smoke out the stack or a miss 99 times out of 100 is a fuel filter might as well start there..........................
