Hello all,
I just had a check engine light occur, ran it on the GAP tool, and it came up with P0442-00 fault code. Any ideas where this small evap leak might be occurring? Prior to the check engine light I had a warning triangle telling me to check the fuel cap, but after filling up, that went away and left me with the fault code.
Possible purge valve?

 

Need to do a smoke test and see if you see a leak.

 

Yeah, I guess its going to be a dealership job. I just had a look at the manual and it says the leak will be between 0.5 to 1.0mm: Following diagnostic procedure

1. Inspect / refit filler cap after smoke test (inspect filler neck for correct fitment to pocket so that filer neck protrudes)
2. Run engine at idle; Using the manufacturer approved diagnostic system, run Purge Valve Self Test (to clean the purge valve)
3. Check that the DMTL module wiring connector has been installed correctly and that the seals around the connector body and individual wires are in good condition
4. Check all fuel system connections are correctly installed and secure
5. Visually inspect purge canister, purge pipes, fuel tank and filler neck for any obvious damage
6. Try isolating the purge valve by fitting a blanking plug to the purge pipe
7. Carry out a smoke test 8. Replace the DMTL module

 

FOLLOWING - Any Updates @Bogwhoppit? What did you find out or end up replacing?

 

Hah well, I had a fiddle with the pipes around the DMTL; dropped the spare, took off the heat shield etc - the heat shield had a massive split anyway from off-roading, so I binned it. I even bought a spare Bosch pump for $65 (Land Rover put it in their box and sell it for $255) ready for replacement, and then bugger me the check engine light went off! I did swap the gas cap for a lockable one from Autozone ($22) and neither the gas cap warning light or check engine light have come on since lol, so it could have been a poor gas cap seal or perhaps a loose clip on one of those pipes. If the warnings return I'll replace the pump, but I'm definitely going to need new canister bolts as the heads have badly rusted.

 

I jinxed myself. The bloody gas cap warning came on tonight for about 5 mins before disappearing lol.....the Landy was reminding me that I am not the master of its domain. The joys of ownership!

 

i have a 2012 land rover sport and im having exactly the same problem. i get a message to check fuel cap twice, and then a check engine light with the same code. when i fill the tank up completely sometimes the car will die, but turns back up immediately. mechanic told me that most likely it will be the canister lurge valve, around 120 dollars new. but i dont want to mess with it before getting feedback. please let me know if you were able to fix yours

 

My 2012 LR4 has the gas cap warning light coming on intermittently along with the check engine light (constantly on) for the past 4 weeks. I had the DTML valve, charcoal canister and new OEM gas cap installed, cleared the codes but the lights remain on. Also experiencing rough start after filling the tank and have to hit the accelerator to keep the engine running, drop it in drive and vehicle drives fine and starts up with no issue until the next fuel up. Anyone have thoughts on what it could be? Thanks

 

Following - Did you get to the bottom of this?

I'm having the same on my 2011 LR4.
Took it into the dealership (which always makes me squirm) - to perform the Recall N623.
Ever since that recall, I have had fuel/evap/check engine related issues...
So far I have replaced: DMTL pump, Charcoal Canister, Fuel flange, O-Ring, Fuel Cap.
Had the fuel tank removed, inspected evap lines, hoses & seals - had the whole system smoke tested about 3 times....
Issue keeps coming back.... But only since the dang N623 Recall....
LR4 had a very happy 12yrs of generally reliable service over 150,000 miles until I took it to the dealer.....

 

Hmmm, trial and error by playing musical parts is expensive (convenience, time and money) and annoying.
And I concur, getting to the root cause is paramount.

We are probably all thinking it. I’ll be the first to say it, then. The fuel outlet valve fixed in the recall… isn’t fixed?
A simple fix with high quality (permanently flexible) fuel tank sealer? Or is it the emissions hoses weren’t correctly replaced? (on the top of the tank)
(Incidentally, on my boat all hoses are double clamped; a nautical standard. Why not on a road vehicle…)