I've got a 2007 jaguar X-Type with the 2 litre ford duratorq diesel engine, with only 70.000 km's (45 k miles) (see my footer).
Cars runs fine, only starting goes a bit rough. It takes a few seconds before the engine finds a stable idle. The engine takes on immediately, but hesitates at a few 100 rpm's for a second or two, three. After that, she runs fine.

Any ideas where to start looking? Fuel filter? Could this be the glow plugs, and if so, best to change all four at once?

Appreciate all input!

 

Check for error codes, or pending codes. Leak back test. Filters if due a service.

 

Bear in mind glow plugs work to START the engine on diesels, not to keep them running. So missing or stumbling while running would not be glow plugs.

 

Changed diesel filter. It appears throttle response might be a tad better, however this might be psychological. Didn't change anything on the start conditions.

Ordered a new dedicated code reader, apparently my old ELM327 (+ torque app) doesn't work on these cars. Was already waiting some time for a reason to do so, so here we are now. waiting for my xmas present. Anyway, the "check engine" light on the dash isn't illuminated (but that doesn't mean it cannot throw a code, I know). I'll report back as soon as I have read the codes.

@ Dell Gailey, car runs fine. Only starts rough. I understand what you're saying, but I haven't completely ruled them out yet at this moment.

 

sounds very much like glow plugs to me. Only change the bad one, they do last a long time. Seems to be exact symptoms on my last motor which constantly burned out the plugs.