The Jag is fixed...your diagnosis?

[Lazzzydog]

On a day out last Sunday my Jag went down into limp mode about 30miles from home. Engine management light came on and a reduced power message on the screen. It is a 3.0 litre V6 turbo diesel auto gearbox. We limped to our destination, parked up and enjoyed our day out. On returning to the car the warnings were gone but re-appeared about 50 yards up the road and all the way home there was a whirring noise as the revs dropped to tick over. Checking over at home I found that the noise was resonating back up through the air filter. This made me suspect an air leak somewhere in the intake possibly a hose or the intercooler but I could not find an air leak! Time to seek help in the form of the local Indie with a code reader.
Here is where the plot thickens. The code pointed to low air intake pressure, i.e. a leak in the system, but they could not find one. Thinking it must be a minute pin hole leak they borrowed a smoke machine and blew smoke into the air filter but there was no leak to be found. They were stumped, but the tech on the job spotted something that provided the answer.
If anybody correctly guesses what was the cause of the problem I will come to Z fest naked with an Ostrich feather up my ar"e.

Start guessing.

 

[hard top]

If anybody correctly guesses what was the cause of the problem

Yeah, Jags are crap .....

 

[Lazzzydog]

I am in no position to argue.

 

[Stevo7682]

I know exactly what is wrong someone at ford made the engine

 

[Dino D]

I know exactly what is wrong someone at ford made the engine

Agree hence the only Fords I’ve owned were powered by VW and latterly by Volvo.

My guess is simple - it’s a jag so either a pipe or slipper got ingested into the intake and caused a blockage

 

[Paul Rice]

Yep know the answer but you and the Ostrich egg just made my mind go all fuzzy.

 

[Mac Romans]

I'm going for some kind of animal interference....

 

[Mac Romans]

Incidentally, I also run a zed/jag combo...

 

[t-tony]

Incidentally, I also run a zed/jag combo...
View attachment 70330

That's a Mondeo Mac .................

Tony.

 

[t-tony]

MAF sensor unplugged?

Tony.

 

[gookah]

crisp bag in air intake

 

[Mnbrennan]

When this happened on my 123d a hole had been put in the intake manifold from the inside out! The mechanic couldn't work out what would have done it!

 

[Lazzzydog]

Just by chance he spotted the bottom radiator hose sucking together as the revs rose and opening up again when they dropped. He removed the radiator cap and all was normal. He fitted a new radiator cap, removed the codes for the 4th time and went for a road test. Unlike the 3 previous attempts all was now normal. They did not ring me but took 2 more lengthy road tests at intervals in the day, still ok. I collected the car and was very doubtful that something so unrelated could throw up those codes but went for yet another long drive and everything seems ok. Why the noise came up through the air filter and why it gave a low intake pressure code is a mystery to me and them. It was an expensive radiator cap at £235 including code reading, smoke test and labour but a much cheaper fix than I was expecting, IF IT WORKS!
If the snow let's up a bit we are due to go up to York today for the UK snooker finals as we've got tickets for Sunday night but thought we might as well make a weekend of it. This will be a good test for the fix as the Jag has got to lug the caravan over the Pennines. To say I am not confident would be an understatement but time will tell.
I have put the Ostrich feather back in its box.

 

[gookah]

I think it could have been a dodgy radiator cap causing the bottom hose to suck itself together.




Edit
just saw your reply... I was spot on

 

[t-tony]

Pinnochio

Tony.

 

[Lazzzydog]

Well done gooka ! You should be a football pundit on telly or a Politician.
The saga was not over though. Despite the snow we coupled up the tin tent and set off for York and all was going well until about 80 miles from home and halfway up the steep Windy Hill climb to the highest motorway point in England on Saddleworth Moor and the reduced performance message lit up and power was halved. We limped to the top and pulled over. I could find nothing obvious amiss so I decided to try to get to the safety of the next service area which we managed to do at a respectable 50 mph despite the reduced power. Fortunately the engine management light did not come on during this time.
With the ignition off the warning message disappeared so I decided to try driving around the service area with the radiator cap removed since the problem seemed to be with the cooling system. Power was restored and all seemed ok so we decided to continue to York with the cap off and hope for the best. We reached our campsite with no more problems and no loss of coolant which surprised me a little. I replaced the cap and retired for the evening.
We went in to York on the bus on Saturday so that we could have a drink and some grub so did not use the car again until Sunday when we went in to York twice for the snooker and no problem with the car even with the cap on. We left the site Monday morning and travelled roughly 150 miles home again with the cap on and the car was faultless. I have come to the conclusion that it is an intermittent fault with the automatic climate control system that seems to be triggered by setting different temperatures for each side of the car but I need it to go wrong again to prove my theory. I will be very happy if it has fixed itself though and behaves itself in the future.

 

[Lazzzydog]

Well unfortunately the car had not miraculously healed itself and last Monday after a short burst of spirited overtaking the reduced power message re-appeared and the Jag went into limp mode. This time it threw up a useful error code and I had the actuator for the smaller 2nd stage turbo replaced at a local indie which hopefully has cured the problem. Sometimes I long for the old days of distributors, points, carburettors and simple diesel injection systems, but only sometimes.

 

[Mac Romans]

I had the same problem and probably the same fault code...and replaced the actuator...twice!

Turns out the problem was the EGR. I replaced that a year ago and it was. Problem solved.

 

[Lazzzydog]

Oh well that's another bill to look forward to then.

 

[t-tony]

I've replaced 2 EGRs on my brothers 2.2.TD. It's a lovely car, .......................................... apart from the horrible noise from the DMF and the pulleys and belt drive. Such a shame. Why did they put a van engine in a "Luxury" car brand?

Tony.