I missed it because I didn't quote your post.... The fluctuation in cat temp (400-900) is normal as the fuel mixture adjusts lean and rich. This keeps the catalyst clean and allows the chemical reaction to occur. It's an emission thing.

 

The DTC has remained and has changed from a stored code to a permanent code as well as a pending code.

I have not found a way to monitor MAF sensors independently at the same time, but in an earlier post in this thread I indicated I swapped the sensors and the air flow rate stayed the same with them one at a time.

If fuel is getting in to the crank case, then a fuel pump would be likely.

How hard is it to test the pumps and how hard is it to replace the fuel pressure sensor?

EDIT: I've run the fuel pump test routine in SDD and it passed with no errors, FWIW, although the odd thing to me without knowing what it is supposed to do is after 1 pump completed its test cycle and SDD moved to the second pump, in the middle of the test the engine stalled, but again SDD said the test was complete with no errors.

 

I think the only way to test the pumps is to do exactly what you did. Stalling is definitely weird. It does not seem like a hard repair. Remove passenger front wheel. Remove splash shields. Remove fuel pump covers. Disconnect unions and electrical connectors, unbolt. Install new tappets and new pumps, reverse order for installation.

The sensor is located right on top of the cross member. Remove the transmission pan heat shield and along the top, passenger side, you will see a small heat shield. Basically, the sensor is behind that heat shield and in front of the gas tank. Looks like there is a fuel line disconnect and electrical connector. However, looking at the sensor, the connect is threaded. Not sure how that works.

 

The MIL finally went away again. I am using a new scanner and found the following DTCs P0089, U0128 (I've had this one for about 6 months - it triggers about once per week), P0346 - camshaft position sensor A, bank 2, P0113 -IAT high input.

Odd SDD does not see these.

 

Interesting. I don’t see any relationship between these codes, except that the sensors all plug into the ECM. Wonder if they’re all on the same connector at the ECM - I don’t have the wiring diagram for this car, but in the 2011 diagram, the CPS and IAT are on the same plug at the ECM. Just wondering if there is some corrosion in the plug - those plugs are sealed up pretty good. Anyway, probably best to check the sensors themselves/wiring at the sensor first.

Seems like any of these three components could cause idle issues.

 

I skimmed through and thought I'd quickly mention a couple of things. I've had a similar issue before (rhythmic rough idle) and I was able to pinpoint it to K&N filter oil fouling up the MAF sensor. Quick cleaning of the sensor stopped that immediately.

Regarding the oil, have you considered a service such as Blackstone Labs to analyze the oil you pull out from the truck? They offer a solid service to help understand what exactly is in your oil to help understand the health of your engine.

https://www.blackstone-labs.com/

 

UPDATE: Well the oil checks out fine though at, according to the main dealer's last oil change at exactly 10K miles, the oil is quite done so if ever the occasion of a next oil change comes about, I am going to reduce the service interval to 5K miles. Funny, Land Rover say it can go 15K miles. As for the presence of raw gasoline, I had a tech give it a sniff and he said it is quite normal on these engines and the way the PCV works, raw gasoline will be present.

Nothing new, unfortunately to report on the erratic idle speed however while search for the fuel pressure sensor (the DTC and MIL come on for this almost daily now) I noticed something that was not present when I did the oil change. The front differential support plate was wet with a light golden oil and the rear of the transmission was soaked with light golden oil along with a drip from the transmission mount. The front of the transmission pan however was bone dry and the rear locking differential and the rest of the underside were all completely dry and clean. So I reckon I have a couple of seals failing as well now.

EDIT: I suppose it could be the transfer case but the back of the transmission is wet too so I reckon air flow would be pushing the leaking fluid from the trans to the transfer case.

 

Thanks for the update - I was going to give this thread a bump to see how you were doing. Sorry to hear no resolution. IMHO, I don’t think the tech is correct about raw gas in the oil due to the PCV. Yes, a small amount gas will inevitably get in the oil (I don’t think the PCV has anything to do with it), but too much and you get dilution, which is maybe why the oil is “done” at 10K. I just had my oil tested and it was perfectly fine at 10K in terms of lubrication. I also cannot smell any hint of gas in the oil. Did the oil report show any gas in the oil?

So, did you have the car being looked at by the tech, and they didn’t mention the oil leak? If so, you need a new shop. Or were you getting an oil change at an oil change shop - is it possible they just spilled a bunch of oil when they were refilling? You mention that it was light golden, so sounds like new oil rather than old oil. Also not sure why you’d have oil (rather than transmission fluid) leaking that far back.

 

Remember, I did the change myself a little while back which is how I found the gasoline smell in the oil and filter, the near black color of the oil and underside of the car was dry. There is always the possibility the main dealer did NOT change the oil last year as they said they did when they charged me for it, wouldn't be the first time I've paid for labour and parts which were not replaced. Oil pan is still dry as is the front of the transmission and pan, it's the area between the rear of the transmission and the oil pan. I found the leak today.

Sadly I've yet to find an independent shop comfortable working on the truck and the main dealers I've dealt with for years are nearly useless. in their defense they typically have 50+ warranty vehicle repairs at any given time and definitely show the signs of being overly burdened and I reckon JLR pushes for warranty repairs to be done quickly and prioritized over customer pay for 5+ year old what are considered vintage and out of warranty). As I've said before the strength of a brand is in the quality of the support.

 

Yes, I remember you changing the oil a while back...just you mentioned having a tech sniff the oil and then the light colored oil on the tranny, so thought maybe you had it back in the shop again, maybe getting another change for some reason.

Can’t quite picture where the leak is - between the oil pan and rear of the tranny - so where the transmission connects up to the engine? Are you thinking rear main seal?