Yes, Red Top Engines is mine. I should have used the same on here. I agree with you, messing around with the adaptation values may not be best. Besides, I really want to find the source of this hesitation. The symptoms are subtle and un-noticeable to a passenger, but every since removing the air manifold it isn't the same. With regards to fuel trims, I don't think they are normal. Over time series, I see fluctuations of long term fuel trim on bank 1 at -7.03, and 0 on bank 2. I see fuel pressure values as high as 15,410 kPa. Desired fuel pressure readings fluctuate from 0 to 10000.
Short term bank 1: -1.56
Short term bank 2: -1.56
Long term bank 1: -7.81
Long term bank 2: -0.781
If it's ok to PM you a table with fluctuating values, you might make better sense of it. I don't think these values can or should be taken at still, rather should be reviewed under performance.

 

They had no idea so I went with the lower priced version and we'll see. They don't keep nor want to keep inventory on hand though occasionally they will do that for me. Their parts system went centralized for the corporation so there's no longer individual parts managers who will work with you. When I receive it I will compare. I can get the truck pretty high on extended airbags plus ramps which's great for fluids and other work/access underneath but if the canister appears too challenging and without and guides I'll likely take it to the dealer. If a replacement doesn't sort this, then I'm doing a tank breather.

EDIT: Meant to add the PCV service is also on indefinite back order due to parts supplier issues.

 

Whine is gone.....

First, I've managed to cut the removal and installation down to about 10 minutes.

The cover came off and though new, too easily for my liking. Inspected everything and re-assembled. Now it's already hard enough being spring loaded and flexible but with the supercharger in the way, bottom part of the cover's a real challenge. This time I rotated the cover a couple of times to make certain the membrane was evenly seated and then snapped it into place. I then used a small pry bar to firmly snap each tab with an audible click. The original time, last week, I only used finger pressure to snap it in and I reckon the problem was some of the tabs, likely the lower most one under the supercharger, weren't fully "clicked" into place and a very small bit of air was squeezing it's way past the cover and membrane, like a filled balloon not tied, with the air escaping making a similar squeal but not enough to induce un-metered air issues and why the fuel trims were finally correct after replacing the failed original.

And now on to the original title of this thread, or at least as soon as the new canister arrives. Hard to believe closure may be near.....

 

As I wait for a new canister, I've tried a few further tests. Multiple times now, after pulling up for a fuel refill, I've left the engine running and removed the fill cap, monitoring idle RPM via OBD and fuel trims for about 5 minutes with cap off. No change. Carefully, slowly added only a litre and instantly RPMs dropped and continued their usual up and down. Don't know if this's helpful but it shows it doesn't take much to induce the problem.

So I've had a thought, why not disconnect the line from the tank to the purge valve and cap off both ends? Remember, when I've disconnected it, the idle problem goes away.

And finally, the whine is back though not as pronounced and not as consistent as before. Land Rover still have no ETA but FCP have them available, though quite a bit more costly than the main dealer by about $20. If the problem's the aftermarket one, I don't mind spending the money for genuine. I've seen several instances where the aftermarket ones worked perfectly so it a bit of a tough call for me.

 

Managed to locate a new genuine PCV kit, likely I swap it this weekend. Meanwhile there are some NOTABLE differences between the genuine and aftermarket. I taken pictures but straigt away main differences include the genuine cover's must less flexible and minor differences in the inside; the valve itself has many differences including dimensions, shape, thicknesses, etc. Enough so I reckon could be a cause for the noise due to the way it would seal. We'll see soon. Meanwhile here are some photos for comparison.

 

If you cap off your purge line, I don’t think the tank will have any way to breath. I believe the only way the tanks vent now are through the charcoal canister and out the purge valve. You would need to somehow plumb in a breather.

It’s got to be the purge pulling in more fumes (or air) that it’s supposed to, which would mean (a) gas in the canister or (b) purge opening when it should not be, or both. The fact that it starts up as soon as you introduce a little gas sounds more like scenario (b).

I wish I had the manual that explained the parameters for when that purge should be opening and what signals it uses. I’m wondering if there is a sensor in the tank telling it to open when it shouldn’t. Seems like you would want it opening only at cruising speed, when there is a little vacuum (but not too much) in the throttle body, and the excess gas fumes would have very little impact on fuel mixture due to the large volume of air/fuel being used.

The only other thing I can think of is that maybe there is something wrong with the filler neck assembly that is forcing fuel to get into the canister even with just a small fill up. Can’t really think of how that would be happening, but I guess it’s possible.

 

Fitted the genuine JLR PCV valve and pleasantly enough it was much easier than the aftermarket, good snug fit stayed in place and snapped firmly shut. Drove a few hundred miles with no noise or whistle or strange throttle body noises.

As for the purge, considering when the line between the tank and the valve are disconnected, the problem goes away. If I plug up the purge input with my finger, whilst the valve is clicking, again, no idle issues. It's only when the purge is connected to the fuel tank. Does that make sense?

 

I think it makes sense. When the purge is disconnected, there are no fuel vapors being drawn up into the engine, so no idle issue. But, if you plug the purge line permanently, the vapors in the tank will not be able to escape at all, and there is no way for pressure to equalize as fuel is withdrawn, at least that’s my understanding. You could remove the purge and just let the line to the charcoal canister be open, or vent the tank to open air some other way (like in the old days). However, the evap leak detection routine will eventually run and will give you an MIL for a leak in the evap system.

Glad you got the PCV straightened out.

 

Still waiting on the canister replacement and of course hoping that's the issue, but if it's not, then considering further options. I've still not found any good directions for for fitting a new one.

 

It’s probably available on landrover’s TOPIX site. You can buy a one day subscription for something like $10 as I recall, and just download the sections you need. I’ve looked around in the past for a free copy of the evap section of the manual as well, and have never been able to find one. As I recall, it’s section 303-13A of the manual.