Hi all, as anyone fitted or had experience of the in line performance chips that can be fitted and do they really work because looking on ebay prices ranges from around £40 to £300/£400 so such a wide price band often makes one think that they are perhaps of little use.I sometimes tow a caravan with my Jag X Estate 2D and alittle extra performance and economy would be most welcome, your thoughts please.
Cheers
Foghorn

 

Foghorn, most of us have not gone with a performance chip as the AWD versions suffer from a weak transfer case and adding more power is going to shorten the TC's life.

MOst of my experience is with truck motors and chips, so, take this for what it is worth. In short, what you pay is going to be relative to what you get. The cheaper ones can be nothing more than adding a resistor to your intake temp sensor which tricks the computer into thinking that there is tons of cold air and therefore runs the car richer, netting some more power. Others get way deep in the programming and alter the timing and fuel programming to improve the efficiency of the car. Since you have the 2L diesel motor, the possibility of getting lots more power is there.

So, do some looking and ask how they are doing the gains. If they are talking about adding in some "black box" in line with a sensor, WARNING!!!!!!!! This is simply a resistor that is tricking the computer. If it is something that replaces the ECU with a new program and goes from there, then that is what I would be looking at. Do not rely on the quoted numbers of power gain as I have found these to be under very limited conditions and can sometimes be very questionable.

 

As the diesel X-Types were never sold in the US, you might want to check out the UK Jaguar Forum too. There's regularly some discussion about re-mapping the diesels with great results.