2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

My Jag (with Ford engine) has a frustrating and dangerous problem.

The idle speed increases when the car is in motion, getting up to 1500 rpm - which when in 5th means acceleration with no input from me!

With the cluth depressed it drops to about 1000, and when the car actually is stopped returns to the correct 800 (with occassional surging)

I have had the local garage hook it up to diagnostics but the car is clean with no codes at all.

I cleaned the EGR valve myself and that made no difference. I would say the problem is worsening.

Could this be a sensor?

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Collos25

Firstly cleaning just the EGR valve is not going to do much you have to clean all the inlet manifold and adjoining pipes.

I would try firstly unplugging the MAF and noting the results,and I believe there is also a fault that can arise on the stepper motor but I am not so well up on the principle.There is also the infamous Turbo actuator a very common fault on these engines could quite well be sticking although the solution to this problem can be very expensive.

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

I will unplug the MAF before the 8 mile commute tonight then. Fingers crossed!

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - injection doc

you may notice if you coast down hill out of gear it will idle around the 1200rpm mark

if you stop the idle will drop, its designed to do so ! what they are not designed to do is to drive in 5th at around at 14-1500 rpm.

Driving a diesel at too low revs in to higher gear will punish the dual mass flywheel.

It will cruise all day at 1700 rpm to 2250 at 70+

If the engine idle speed shuts down too low its makes them kangaroo at low speed.

They are fitted with an antistall device that is linked to reverse gear & that raises the idle, I suspect the issue could be related.

Edited by injection doc on 21/02/2013 at 19:42

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Collos25

I have had two Jaguar diesels and never experienced the above situation ever in 200kkm.

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

Thank you very much for the input - really appreciate your help.

I can see tyou points re the coasting and stopped idle speeds and yes that is what min is doing.

What is off putting however is the acceleration through 1500 rpm on its own when in 4th and 5th.

I have noticed that the idle does raise when reverse is selected. Can you think of a way I could isolate/test that to see if this is the problem?

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

Unplugged the MAF last night - no change :-(

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - madf

"My Jag (with Ford engine) has a frustrating and dangerous problem.

The idle speed increases when the car is in motion, getting up to 1500 rpm - which when in 5th means acceleration with no input from me!

With the cluth depressed it drops to about 1000, and when the car actually is stopped returns to the correct 800 (with occassional surging"

Sounds to me like a faulty throttle position sensor and/or a carbonned up throttle /air inatke.

Neither would register any ECU faults. Dismantling job .. and a proper electrical test on the throttle position sensor - checking voltages etc with an oscilloscope...

EDIT: your local garage are incompetent.

Edited by madf on 22/02/2013 at 13:45

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

Thanks all. Plenty of options there to consider.

Just thought I'd ad another point - perhaps to help isolate which problem to prioritise;

On the motorway at the weekend I found that the car overode the the cruise control on a few instances. i.e. set at 70 and the car contined to rev out beyind 2000 rpm towards 80 before I applied the brakes.

Does this help eliminate any of the possible causes?

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - dieselnut

" On the motorway at the weekend I found that the car overode the the cruise control on a few instances. i.e. set at 70 and the car contined to rev out beyind 2000 rpm towards 80 before I applied the brakes. "

That sounds like the engine is running on fuel other than that supplied by the injectors.

If the car was accelerating past the set cruise speed the ECU should/would have cut the fueling. Check your engine oil level isn't above the high mark. If ok, I would check the turbo oil seals arn't passing excessive oil.

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

thanks dieselnut. 2 good places to to check.

Is the turbo seal inspection a diy job?

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - dieselnut

Is the turbo seal inspection a diy job?

Depends how accessible it is. You would need to remove the inlet pipe to give access to the turbine spindle. The spindle should spin freely with no more than just discernable play.

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Collos25

Unplugged the MAF last night - no change :-(

Does that not tell you something.It could be that the MAF is faulty or that the wiring to it or the plug is faulty all three common problems on this engine.Having a faulty non operative MAF will give exactly the problems you describe.

Edited by Collos25 on 06/03/2013 at 13:37

2005 Jaguar X-Type 2.0d - Jaguar diesel idling high, especially when driving - Moshimonster

@Collos25 - I will admit I had assumed that by discionnecting the MAF we'd be looking for a change to the performance as a faulty one would have had at least some effect. But what you are saying is logical - it is is not active the car could run as if the MAF were not on-line.

I will look into this.

Thanks

 

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