My understanding is that these codes are usually due to "pirate air" influx between the MAF and the TB, or other vacuum leaks. I used fuel trims to verify a likely vacuum leak at idle, and an ultrasonic detector led my to the PCV and the adjacent hose connection leading to the TB. I replaced both but still read a leak there, the hose replacement was OEM branded but appeared pretty stiff so maybe the o-rings had hardened? Anyway, I disassembled and reassembled using some Ultra Black rtv, and now need to wait 24 hrs before restarting. Any other known causes for these lean bank codes?

Preparing for smog on my wife's XK the battery was low and after jump starting all the monitors needed to initialize so after days of driving cycles it threw these two codes as the final monitors reset (O2 sensors and EVAP), never had thrown any codes in the 7 years we've had the car. Replaced the fuel filter (hopefully), bought a better code reader to check live data and freeze frame data. Could it be the O2 sensors are too old? They were the last monitor besides EVAP to set after about 500 miles total driving.

 

The O2 and EVAP take awhile. There are ways to shorten it some. See post #6 in this thread;
Drive cycles

 

Do you have a Gas/Petrol smell on start up? I had noticed this on mine when I got it, its common for the O-rings to fail on the fuel pressure dampers. You can buy the dampers from Injector planet in the US for $49 each, Jag sells them here in the UK at £172 each or you can replace the fuel rails at £1400 each. What this mean is your fuel rail especially like I did recently on full send cannot get enough pressure I think its holds at 56psi. This will cause the lean bank and potential engine miss fire error codes mines done this and has the codes. I have cleared retested and confirmed the same. Its the ethanol in the fuel that eats the O-rings, another post here shows you actually do not need to have dampers as on member removed and the car work fine and does not have to worry about future leaks and problems.

Mine are being replaced next week will advise if this clears the lean and misfire problems.

 

I have had a gasoline smell on start ups and I have traced it in my case, to overfilling at the gas pumps. Afterwards it takes a while to work thru to normal. There may be other reasons as well for your codes.! I have in the past stopped an O2 code, by using an extender between the exhaust and sensor. (Volvo S60R)

 

1.Thanks for the link on the monitors.
2. No real gas smell on start up only after warm up at idle, but will keep in mind.
3. Start up today: problem remains full inspection of replacement hose with ultrasound detector reveals additional leaks at ends of hose where it meets connector ends. TB end of hose less leak than before, other end and PCV still as bad as before. While running at IDLE LTFT BOTH AROUND 18-20; AT 2500rpm 0-2 indicating vacuum leak still the issue.

Ordering O rings to recondition original hose and rings on PCV into cam cover 14mm ID x 2.65mm Cs (2) and 16mm ID X 2.65mm cs.

 

Have you tried watching STFTs as you spray a little at every possible place in the engine bay?

You can sometimes get away with water but a gas (propane etc) is better - just let each squirt clear before doing another (you're not trying to cause a fire!).

STFTs go mad if you find the leak.

 

That is up next, my Autel MK900bt will let me watch trims while working the engine compartment, hopefully with the help of my son the engineer, thanks for the tip on the short term trims. I have learned a lot from reading the other theads (including your posts) on this issue. Thank you (long time lurker, first time asking). Steven Sather

 

My son got home this afternoon, and we took a propane torch (unlit of course), and verified the leaks we found with ultrasound detector. STFTs did go crazy in opposition to the LTFT,s, particularly at the base of the PCV and the hose end adjoining it leading to the TB. The new pcv I bought cheap leaks at the base, I have a Genuine Jaguar version ordered, but I am impatient and may try putting o-rings with a slightly thicker cross section on it; 3mm instead of what looks to be 2.5mm. Any thoughts on this?

By the way, the ultrasonic leak detector seems to work really well for this it only cost about 30 dollars US, and works better than my ears (lost high frequency hearing) it emits a signal like a Geiger counter in a set of headphones, clicking signal increases in frequency the closer to the leak you get, only one knob for sensitivity control. Very handy.

 

Can you post a link to the detector, or post the name and model number? Lots of old and abused ears out here.

 

Vanlison ultrasonic leak detector for HVAC/Automotive/Industrial use 38 - 42kHz frequency range Amazon (US)
Couldn't figure out how to post the link from my old tablet, May try from PC tomorrow.

 

Ooh, a new tool... thanks for the info

 

try this link

 

Ok - the Genuine Jaguar PCV got here today, Put 14mm ID x 2.65 CS (cross section) o-rings on the original hose from PCV to TBody, installed both with some silicon grease, (in the process broke some very brittle 4mm OD vac hose, fixed those after a trip to the parts store for 4mm ID hose (smallest they carry) which I fitted to existing remaining hose ends with heat shrink tubing), leak reduced according to idle LTFTs down from +20 on both banks to +12-15, engine light went away but not happy with limited improvement. Took o-rings off of new PCV (only 2.5mm cs!) installed 16mm ID x 3mm cs new o-rings and reinstalled to car, this reduced idle LTFTs to +1.6 to 2.3. Much better but ordered 16mm ID x 3.5mm CS to try to get to zero at idle. Also got new gas cap to try. Any idea how many warm up cycles until lean codes might go away?

 

LTFTs under 5 are OK. Under 2 is great but not needed.

 

Good to know that LTFTs are ok at 5, still some maintenance items to be done. Been in a bit of post retirement fog, time to get back at it! Next big project will be the cooling issues on 2012 XF. Thanks Jag V8.

 

"The new pcv I bought cheap leaks at the base" I was unimpressed with my replacement PCV. Compared to the old one and it didn't do much of any thing. I suggest larger O rings..
For your XJ try waterless coolant!

 

Normal to see fuel trims at a slight positive, up to +10% on cars that weren't originally planned for E10 fuel. It's literally less fuel per unit than pure gas, so there is a slight compensation to be expected, which the car is fine with. Usually you're required by law to put a CEL on over 25% correction, but many OEMs will set faults at less than that as it's still indicative of an issue and can help with repairs.

 

For some reason, that link is not working for me. It's just going to a blank tab and then closing automatically.

If anyone else is having issues, here is a fresh link...

 

lol. The original is working now. Scratch my last message. My cookie settings got changed.

Please return to your normally scheduled programming...

 

After fixing the vacuum leaks and fitting the new PCV with 16mm ID x 3.0mm CS O-rings and running a can of BG44k Platinum through the tank and 4 days of drive cycles all monitors set and passed the California smog test, on to the cooling system on my own XF. At least my wife is happy now - the XK is done for the moment.

Thanks again all!