I was wondering whether anybody with an S-Type diesel has noticed that it hesitates for about one second when opening the throttle from stationary?

For example, wanting to do a cheeky little inject into a roundabout only to have the car sit for a second before exploding into life?

Or, on a trailing throttle, at low speed, hit the loud pedal only to have to wait for it to decide to respond?

Any  ideas please?

hi paul

saw this http://www.jaguarownersclub.com/forums/topic/8674-diesel-engine-problem/

Thanks Joe.

I've read it through. I don't think it's related to the problem, if it is a problem, I'm seeing though.

hi Paul

the only other thing i can recommend is if this has recently started and is getting worse is

A lot of people recommend Terraclean, which is suppose to clean the the whole fuel system and exhaust

the other thing to look into is that I've seen a few people saying they cured hesitation on the diesels by swapping the turbo actuators, which are apparently electronic and are prone to failing

do you get any fault codes

also on my s-type r, when you use the IDS software, under special applications there one called "flight control" if this is enabled and running, it logs all engine sensors, voltages, car speed, gps and more, looking through this data might show up a fault with a sensor, but I'm not sure if this is available on the diesels

cheers

Joe

Thanks Joe

Hi Paul,

I have used Terraclean and found it quite beneficial, both in performance and fuel economy.

As an aside, I was in Bergen last week and saw a Black S type with Leaper - I could not get a photo as I was on a 'bus.

Regards,

Peter.

An update.

Thanks to Denis, my car's throttle body and MAP sensor were replaced today. The originals were gunked up to the eyeballs.

As a result, the delayed throttle response has been sorted :)

On 7/2/2016 at 9:03 PM, Raistlin said:

An update.

Thanks to Denis, my car's throttle body and MAP sensor were replaced today. The originals were gunked up to the eyeballs.

As a result, the delayed throttle response has been sorted :)

Paul, any chance of expanding on this a bit.  I'm not massively mechanical by nature.  Is this a big job?  What sort of cost is involved.  I have had this hesitation, usually exactly as you say...a cheeky squirt onto a roundabout only to find your ar$e hanging in the wind for a second while the big cat girds it's wotsits for the leap!

 

I had mine booked for a Terraclean but the company did not have enough of the connectors to hook the stuff up to the old girl's fuel system.  :-S

Adam,

I got a second hand Throttle body from fleabay as mine was damaged (cracked) and repaired anyway. The MAP sensor was included. Denis then took quite a considerable time to clean it all out internally, ready for installation.

The removal of the throttle body took about an hour as we were both a bit unsure as to whether the exhaust gas pipes to the throttle body were separate or continuous. In addition, the exhaust gas pipe clamps took a moment or two to work out. The exhaust gas pipes are, in fact, separate but they are very much handed and you need to make a note of their orientation, perhaps removing and cleaning only one at a time. There were various O rings involved but they all seemed in good condition so were re-used.

There are other embuggerances (with acknowldgement to the late Sir Terry Pratchett) such as the coolant expansion bottle needing to be displaced and the outlets of the throttle body needed some persuasion to let go of the inlet manifolds.

Having removed the throttle body, Denis set to work to remove the carbon deposits from withinh the exhaust gas pipes which was a horrible job and I suspect that a lesser man might have given up. However, he didn't give up and completed the decarbonisation.

Having gained experience from dismantling, assembly seemed much quicker. Again, the the throttle body outlets needed a deal of coaxing to go back into the inlet manifolds.

A test drive proved that the time and effort expended by Denis had been well worthwhile