So I was told by a private muffler shop, plus the local Jaguar dealer that check engine light was on/ running lean condition due to leaking PCV diaphragm. I also pulled the codes myself and verified the running lean condition. I take the vehicle to local Indy Jag repair shop, they replace the PCV diaphragms. I drive the vehicle for 10 minutes, and the check engine light is back again. Is it possible the shop didn't clear all code data? 2010 XF Supercharged. Thanks.

 

Awwww man that sucks, did you check the PCV hose on the passenger side that runs above the valve cover? The ends have issues with cracking allowing air to seep in. If nothing works you’ll have to get a smoke test and get your O2 sensors checked out. Does it have a rough idle? Does anything feel off?

 

 

The engine is definitely not running just right ,can tell on cold starts, will see a bit of rough idle. I will check that hose, would think the shop would have checked it since they were working right around that same area, and they knew the nature of the issue (vacuum leak) etc. I will at least see if it's still throwing the running lean codes, verify hose is not leaking. It will go back to shop after that. Thanks again for all the info on this repair. Most helpful.

 

I obd2 scanned the vehicle, P0171 and P0174 again. Drove the car 5 minutes after, check engine light cleared. Let the car sit, drove it again for a solid hour, no check engine light. Rough idle is clearing up as well. At the moment I am convinced management systems had to recalibrate after the repair.