I have Check Engine Light on with P0171 and P0174 and intermittent loud whistling noise at idle. It goes away with engine revs or oil filler cap/dipstick removals. I've been through many sites and learned that it could be related to PCV valve but I couldn't find any PCV valve thingys on LR2 sites. I now wonder LR2 even has PVC valve. Please help me with the issue. Mine is 2008 LR2 SE 87K miles on it. I don't know if it's coincident but I get the whistling noise after I cleaned the MAF sensor and relocated the air filter to resolve the codes. Thanks in advance

 

What did you mean when you said you "relocated the air filter"?

 

Sorry for my bad wording. I just pull the filter and rotate 180 degree and put it in.

 

Understood on the air filter repositioning.

Did you clear the codes so the only remaining problem is the whistling?

 

I've erased the codes several times but not able to clear it yet.

 

It may be a vacuum leak. If the whistle noise started after you cleaned the MAF, you might not have put it back together with a tight seal. With the hood up and engine running, try to listen where the whistle noise is coming from.

 

I've learned that it might be a vacuum from the crankcase according to a BMW forum. I'm trying to locate the PCV valve for LR2 so I could try to clean/replace it. I thought I could find the related thread for this forum. My LR2 has no issues so far other than the noise and CEL.

 

I don't believe it has a PCV valve. Please let us know if you learn differently.

 

Okay then. Let's forget about the pcv valve thingy.
I have the loud whistling noise at idle. Two mechanics so far couldn't figure it out where it coming from. It disappears when I pull the engine oil cap or dip stick. What do you think the cause?

 

A common method for finding a vacuum leak is to introduce white smoke into the system (while engine OFF) and then watch where it comes out. Youtube has a lot of videos showing how this is done.

I suggest you call around to your local shops and ask them if they have a smoke machine and how much they charge for a vacuum leak smoke test. Please post back and let us know how it goes.