It’s a good idea but it’s very important what detergent you use. On my another car I used a detergent for 5mins as recommended and the crankshaft rear seal started to leak! Maybe a cheap semi-synthetic oil is better than an expensive detergent.

However the engine that I rebuilt was very clean after 148000 internally Only pistons had a bit of carbon build up. So, given above two experiences I have, I never do an engine flush unless I am dealing with a car that has not been serviced properly. I like intake or injector cleaners ( or a higher quality fuel) though as I have seen it’s very easy to clean them in early stages compared to when they build up and cause you a problem. You cannot even take them off with a sand paper. Let alone some additives or spray.

 

Yes also correct to use a less expensive oil as a flush . i use techron injector cleaner quite regular works fine but have not taken them of to check how clean they are

 

[QUOTE=davetibbs;2240946]I think you will find if you read this thread that they don't. The V8 engine has no oil pressure sensor.[/QUOTE

I wonder how they detect low pressure then. There is a low oil pressure warning light so I wonder how it is triggered.

 

An extract from a very interesting article on oil weights.

 

So you are suggesting that oil gets thicker as it gets hotter? It is not that simple. The weight changes but so does the temperature. Hot oil is always thinner than cold oil. That is why you warm the oil before draining it.

https://www.minimania.com/Motor_Oils..._Misunderstood

 

Sorry, I should've been more specific: the V6 engine does have an oil pressure sensor, the V8 engine does not. My theory for this is that the threaded hole used for the sensor in the V6, which is just blanked off with a threaded plug in the V8, is too close to R/H exhaust manifold with 4 exhaust ports (vs 3 on the V6), and maybe Jaguar saw reliabilty problems with the sensor on the V8 engines due to the heat?

Either way, the technical training and service manual do not mention any kind of oil pressure sensor, and just contain a table of reference oil pressures at different rpms/engine temperatures, which can be verified with the official Jaguar service tool which is essentially an oil filter cap with a threaded port on the top for connecting a pressure gauge.

I repurposed the threaded port on the side of the block with a braided hose to a pressure sensor mounted away from excess heat to run my custom oil pressure gauge which has worked quite well.

 

Dave, my engine is in a RR Sport V8 SC and the manual shows a low oil pressure warning light in the dash cluster although I have not seen it come on before starting. Does your Jag manual not show one? I realize there is no sensor so how would they detect it I wonder? Could they do it any other way?

 

I am sure 4.2 V8 has it. It sounds very strange if 5.0 does not. Bear in mind it is not really a sensor. It’s normally referred to as pressure switch or sender. Because it acts as a switch. It will ground the wire when pressure is below a certain level. E.g. 0.5 bar or 7psi. It will not monitor the actual pressure. So long as the pressure is above 0.5bar you won’t see any warnings. So it will not help when you have a blocked oil passage on crankshaft due to spun bearing or a clogged up filter but it will help when you run out of engine or your oil pump fails.

 

Yes, my 2010 Jag manual shows an example low oil pressure warning light in the dash cluster. I believe I read somewhere that theoretically there are ways of estimating a low oil pressure condition by evaluating cam phaser positions but I'm not convinced this is implemented - not least because I saw no oil pressure warning lights when my pressure dropped enough to spin bearings, so it certainly didn't work for me.

I don't know why they would include a screenshot of an error message that can't actually be displayed, but I've read that later (2012?) manuals came with an addendum that stressed the importance of regular oil checks. They may have even decided that even though only some engine types had a oil pressure sensor (3.0v6 and diesel, I'm guessing) they would still include the message in the manual.

 

This is the part number and diagram of oil pressure switch for your engine:

5.0 S/C oil pressure switch

 

Yes I found that listed on several dealer sites but it is a mistake, that part number is actually the fuel pressure sender (high) on the end of the fuel rail. Dave is correct, there is no oil pressure sender/switch. I completely stripped my blown motor so I would have found it.

https://www.jagroverland.com/jaguar-...ator-aj812513/


If you want a laugh.....the driver said he never heard any bad noises!

 

Wow!

did you use a new block or changed the engine?

 

Bought another RRS from Copart and swapped engine, after rebuilding timing gear, water pump etc.

 

So just to update on the issues I've been having... My Mongoose cable arrived, and I noticed with engine off, I got the following readings:

by Chris B, on Flickr

If I'm interpreting this correctly, this indicates the exhaust cam on bank 1 is not able to get into the locked position when oil supply is removed (engine off). In any case, the two cams should be near as dammit the same if working correctly, but they're a little different. I haven't tried with engine running as I couldn't find how to show live OBD data within the software. I'm sure the function is there, I'll just have to spend more time getting familiar with it.

Today I've stripped the front of the engine down and have not found any debris in the camshaft filter. Additionally the filter and oil passages that I could see were wet, which doesn't suggest there's any lack of oil supply in the area.

Now I'm thinking the VVT itself is at fault. I've taken the decision to put the engine back together with a previously removed exhaust VVT (I only replaced them during the rebuild as a precaution in the first place, there was nothing to suggest they had actually failed). Some might find that a strange decision, but I figure that as there appears to be history with these being faulty brand new out of the box, I feel a used but working item might be a safer bet. I'll report back when it's running again...

 

any fault codes from SDD?

 

So, with a used VVT installed the P0017 cam/crank correlation code and restricted performance is now gone! I'm delighted with that, as I've been stuck with this code for months. @DaveTibbs, it seems the likelihood of getting a bad VVT out-of-the-box might be more common than first thought! Unbelievable. Thanks a million for all the brilliant info you've added in this thread.

However, one issue remains, spoiling all the fun. The MIL is illuminated every 3rd engine-start, and my OBD II scanner reports the following:

Address 7E8: 2 Faults Found:
P0341 - Camshaft Position Sensor (G40): Implausible Signal
P0341 - Camshaft Position Sensor (G40): Implausible Signal
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Freeze Frame Data for address 7E8
PID02 DTC that caused freeze frame data storage: P0341
PID03 Fuel system 1/2 status: Closed loop, using O2 sensors
... Closed loop, using O2 sensors
PID04 Calculated load value: 56.1 %
PID05 Engine coolant temperature: 91 °C
PID06 Short Term Trim - Bank 1: 0.0 %
PID07 Long Term Trim - Bank 1: -4.7 %
PID08 Short Term Trim - Bank 2: 0.0 %
PID09 Long Term Trim - Bank 2: -5.5 %
PID0B Intake Manifold Absolute Pressure: 40 kPa abs
PID0C Engine RPM: 583 /min
PID0D Vehicle speed: 0 km/h
PID0E Ignition timing advance for cyl #1: 12.5 Degrees
PID0F Intake air temperature: 67 °C
PID10 Mass Air Flow: 6.10 g/s
PID11 Throttle position sensor: 13.3 %
PID1F Time since engine start: 18 s

I've swapped the CMP sensors over (within the same bank) but it made no difference. I've compared the voltage across the sensors on a multimeter and they're all about the same (2.4-2.6v engine running). I'm likely to buy an oscilloscope soon so I can check the waveforms. Should I expect to see perfect square waves?

Does anyone have any experience of this code?

I will connect with SDD on Saturday morning, in hope it sheds some further light on the above...

 

Do you know the torque specs for all the bolts for the crankshaft caps

 

Yes, specs attached. Look for M10 and M8 Main Bearing cap stages. Bolts are torqe-to-yield.

 

I’m in the middle of rebuilding one of these motors and was wondering if you were able to get the stock ring gap specs. Also was wondering if you knew anything about these parts to this machine shop took out of my heads. They had damaged one so I really need to try to find another one

 

They're anti-drain valves for oil, and the part number for a new one is AJ811497. I'm afraid I was never able to find stock specs for a lot of the engine internals.