I have a 2004 Volvo XC90 with 140K miles and the check engine
light is on. I took it into Firestone and they said the code indicated Cylinder 4 is misfiring, the catalyst system efficiency is low (said the catalytic converter probably needed to be replaced). But then he said the turbo is blowing oil and leaking and that should be fixed first, then reevaluate the rest of the system again. They don't do that kind of work and they referred me to another auto shop.
JA: Does the light stay on, or does it blink?
Customer: Stays on. Been about 3 weeks now. First thing I did was replace the gas cap...
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: I looked at some videos online. I think the turbo is way above my level of expertise. I'm trying to figure out if $2000+ is a fair estimate and if so, is it worth keeping the car. It doesn't leak oil on the ground, and generally seems to run fine other than the engine light. I've kept it regularly maintained.
JA: Anything else you think the mechanic should know?
Customer: I don't think so.