Thanks for your advice. I'm going to have my mechanic do it. However I'm still wondering a issue of the intake vacuum leak makes an intermittent whistling noise which is at idle only and goes away with pulling a oil cap or a dipstick. If it's from positive crankcase pressure build-up the smoke test wouldn't catch it.

 

BlueSky, I'm having the exact same problem on a 2008 LR2. Did you ever figure out the problem? Mine is so loud at idle I can't pinpoint the location. Carburetor spray around intake manifold silenced it once but could have been coincidence. My engine has to be very hot before noise starts. I'm thinking intake manifold gaskets but don't want to dive in if it's something simpler.

 

I had the same problem and it turned out to be a valve (pcv?) that went bad around the intake manifold. My shop was able to locate it by taking off engine cover. I'll see if I can find the work detail and let you know which part was replaced. It wasnt very expensive and didnt take long to swap out.

 

Hey guys, I got it fixed. If anyone else is having the problem of loud whistling at idle on an LR2, the crankcase vent valve has failed and sucks vacuum directly into the engine block. The whistle is from air seeping in around the camshaft and or crankshaft seals which is bad as dust and dirt will be drawn into seals potentially causing undue wear. The whistle is very high-pitched and sounds like an idler pulley bearing going bad. As BlueSky said, you can pull the dipstick or remove oil cap and whistle will stop as it relieves the negative pressure inside engine block. Smoke tests will not find this leak in a traditional vacuum leak test with engine off.

The crankcase vent is an integral part of the black plastic engine cover located back near the firewall. Diaphragm inside the valve goes bad and causes vacuum leak. Replace entire cover to fix the problem. It is about $180 part from Land Rover, looks like a valve cover on traditional engine and is easily replaced by removing torx head bolts and swapping out. Rubber gasket was included with my new cover.

 

I work at a dealership and my 08' Land Rover LR2 @ 87,xxx miles just started doing the whistle while idling this this past weekend.

Had a one of the mechanics take a look at it and from my understanding the PCV Valve is whats causing this whistling sound. Apparently over time the engine has a build up of oil and the part connecting it to the dipstick is making that sound because it needs to be replaced. Everytime he lifted the yellow dipstick thing the noise stopped. That said the PCV Valve is built in with the Cylinder Head Cover and needs to be replaced all together. See link below for what it looks like and what's needed:

#LR023777: Land Rover. Engine Valve Cover. VALVE COVER.

** This was the best link I could find that looks like what my mechanic pointed out/printed out for me from the parts guys.
** When looking at the link scroll down to #4 & 5 this is what my mechanic told me it is. Either way I would have a mechanic check to make sure, but the part cost me 136.00 from my part guys

 

I may be wrong, but I don't think the LR2 has a PCV valve. Which of those items in the diagram is the PCV valve?

 

pcv valve is built in with the cylinder head cover. So I just bought the whole part from my dealership for 136$ and getting it fixed Monday. For now what I can do in the mean time to stop the whistling at idle is to take the dipstick out just enough so that the 2 "o rings" are out and whistling stops. Below is a photo of what I just ordered to fix the whistling and a diagram my parts guys printed out to show me where the PCV Valve is basically located.

 

My sister-in-law had this exact issue, and a Google search brought me to this thread, so we had a good idea where to look.

She bought the valve cover (pcv valve made into it), and I put it on in about 20 minutes. Around 100 miles later, the "check engine" light went off.

It was super easy, and worth doing on your own. I made a DIY video on it in case anyone else wanted to take it on.