I have a 2005 Xc90 2.9L. I recently had to have it towed to the volvo dealership. the engine would crank but would not idle enough to keep running. They replaced the Air hose from the turbo to upper air manifold. When I got it back the system message read reduced engine performance and eventually it happened again (would crank but not stay cranked) This time though it cranked 24 hours later. The check engine light is on and read 2178 and 2180. could someone please tell me what Long Term Fuel trim lower limit means and what it involves to fix it. Im going to take it back to the dealership or find another mechanic but I dont want to be taken advantage of and charged an arm and a leg because Im female. They also said that I needed a new upper air manifold and upper engine mount but did not replace it at this time. Would replacing that fix the problem?