I changed the oil in my 06 with the 4.2 V8 about 3K miles ago. I noticed today that she was down a quart, and, I topped her off again. She's got 61K miles on her now, and, she doesn't appear to be leaking oil anywhere. I'm been running Castrol GTX 5W-30 in her since I bought her @ 48K miles. Should I be concerned about it, or, is it normal for her to use a bit of oil in cold weather.

Regards:
Oldengineer

 

OldEngineer, with modern day motors, most manufacturers will claim that up to a quart of oil usage per 1,000 miles is "normal". So, using that methodology, you are still good. Granted, to me, that is somewhat high. I would first start with a new PCV valve to see if you have a bad one and it is simply just letting too much oil by. After that, doing a leak down check will probably be your best bet. If you need more information on this, let me know.

 

Although many would say that using a quart of oil in 3,000 miles is normal in a car such as this one, I agree that your case sounds a bit on the high-usage side. Our S-Type has the Duratech 3-litre V6, I change the oil & filter every 6,000 miles, I also run Castrol GTX 5W-30 conventional oil, the car will have about 40,000 miles on it when my wife returns from Tampa next week, and our engine uses no oil between my selected maintenance intervals....

 

Since this is the first time the car has indicated any oil usage since I got it, I'll go ahead and change the PCV valve. I'll have to figure out where it's at on the 4.2. Thanks for the advice.

Regards:
Oldengineer

 

Hmm - Checked a bunch of jag parts sources on the internet - apparently the 06 4.2 doesn't have a PCV valve per se - nobody lists one for it. Near as I can tell there must be an orifice in the fitting on the driver's side valve cover that has to be cleaned periodically. Can one of you techs confirm??

Regards:
Oldengineer

 

Doesn't cover as late as 06 but for 04, jtis says:
On vehicles fitted with a 4.2L engine the positive crankcase ventilation (PCV) system consists of a PCV valve, and two PCV hoses. The PCV valve is mounted on the right-hand valve cover and a hose is connected between PCV valve and the throttle body elbow. The PCV valve regulates the amount of ventilation air and crankcase gas supplied to the intake manifold and also prevents backfiring into the crankcase. The left-hand valve cover PCV hose is connected to the air cleaner outlet pipe.

Not heard of how (or how often) to clean it

 

PCV valves are cheap parts. Most say to change the PCV valve out every 60K miles, I try to do it a bit more often than that.

 

I'm going to call the dealer this morning and see what the parts guy can tell me about a PCV valve. I saw the references to it in my JTIS info as well, but, mine only goes up to the 03 model. Will report back after I talk to dealer.

Regards:
Oldengineer

 

Update: I talked to the parts guy at my local dealer about a PCV valve for my 4.2. He indicated that he had never stocked or sold one, but, could order it for me for $55. I decided to try cleaning it instead. The thing he's calling a PCV valve is a large 5 inch diameter plastic valve mounted on the right valve cover. When I got it off, and, looked inside, all it appears to be is an anti-backfire valve. There's no orifice in it. I popped off the line to it, and, checked the port going into the intake as well - no orifice there as well. I also took off the line going to the left valve cover as well - no orifice or valve on that side as well. Anyway, the stuff was pretty clean inside, but, I washed out the two hoses and the valve with some cleaner anyway, and, put everything back together. I found no evidence that the system was sucking oil into the engine. We'll see if my cleaning efforts did anything.

Regards:
Oldengineer

 

It's still news to me that the PCV is any kind of trouble or needs any kind of attention on the 4.2. It doesn't appear to have been an issue in older posts here or the UK forum so I wonder if it's maybe not actually an issue.

I doubt it accounts for your oil usage but then I have no idea what does, sorry

Except.... if it didn't use any before you changed it and does now (or: appears to), could it be somehow related to that? Just wondering out loud here.

 

surly if there is no bluish smoke coming from the exhaust then you are not burning oil in any great quantity, in the old Audi 100s it was normal for them to use about a pint per 1000 and that was in the 70s , saying that I have not noticed any great oil usage in mine between changes and its done 130k, I change it every 6000 miles (UK)

 

$55 for a plastic so-called PCV valve?! That belongs right up there in the Hall Of Shame with $60 for a litre of mineral oil-based ZF transmission fluid. No wonder the luxury car segment continues to teeter on the brink of disaster....

 

I'm sure it can be had for much cheaper off of the internet.

 

I never was able to find one from any of the internet Jag parts guys. After getting it off and looking at it, I don't think there's anything wrong with mine.

Regards:
Oldengineer

 

I'm not seeing any blue smoke at all. I've been changing her oil and filter at 5K (US) intervals - using Castrol GTX only. She'll need another oil change in about 2K miles. We'll see what happens to the oil level in the meantime.

Oldengineer