Hey gents,
I currently have an intermittent vacuum leak on both banks that I am trying to hunt down. CEL comes off and on every few days, so it seems to be fairly intermittent. I went to a shop to get a smoke test done and you could see it was pissing smoke out of the PCV valve. I replaced it but still have the same issue. I noticed there seems to be an oily residue on the hose leading to the pcv valve, so I thought I might replace that next. I will also add that I occasionally smell gas as I am driving along, which leads me to suspect something with the EGR system. Would that add up? I may end up just having another smoke test performed, but have been thus far avoidant of doing so because of the ludicrous $100 that shops around me charge.

 

For around $100, you can buy your own smoke test machine on Amazon now. I've got one that basically looks like a syphon cup from a paint sprayer but is pre-Amazon, assembled by a guy who made them in his garage nights and weekends as a side business. Works great if a little bit fiddly (my only complaint is that my air hose is heavier than the unit itself so it doesn't hang vertical without help to keep it straight and if I sit it on a table it will turn over without help to prop it up). They have some much better, more compact and professional designs that are quite affordable now. Some don't even require a compressor and have their own little pump built in which is what I'd get now if I didn't already have an antique. But no more often than I use it, I'd rather fiddle with keeping it vertical than pay labor rates at a shop to do the tests for me.

 

Put the MY of the XF and motor in the signature or in the body of the text. We need to know which car you're wrestling with.