[Perry]

Well, I have had a misfire/slight hesitation under hard acceleration for a while now and it has been getting gradually worse. Car always started 1st turn every time and is a very smooth runner. I suspected a vaccum leak somewhere and went through a whole can of carb cleaner, spraying it over the running engine in all the suspect areas (throttle body, etc.) but could detect no change in engine note. MAF only 1 year old, but I cleaned it anyway! All relays removed and contacts cleaned. No codes on the OBD reader.

So, I took it to 'Jagcare' in Portchester this morning and they asked me when the plugs were last changed. I admitted that I couldn't say as I have a fully stamped service book but no actual paperwork for the 60,000 mile service, which would have listed if the plugs were changed as per the schedule. As the car's mileage is now nearing 98K I went ahead and changed the plugs anyway. Interestingly, the old NGK Iridiums were a good colour but the centre electrodes looked extremely 'blunt' in shape when compared to the new ones, and the resulting gap quite large. It is possible that they were not changed at 60k. :?

Anyway, Bingo! Hesitation under hard acceleration now gone.
(Thanks again Jagcare)

 

[DaveV8]

That's really good news, glad you got it sorted 8) Wish mine was just a set of plugs, mine looks like it's the fuel pump ... Does the same type of thing though, hesitates when you kick down quickly, but mine won't go above 4000rpm, coughs and splutters after 4000rpm!

 

[Perry]

Sorry to hear yours not sorted yet Dave. Hope the new pump, when fitted, sorts things for you.

 

[DaveV8]

Thanks mate 8)

I've heard these XJR's are like lightning speed when kicking down at 30mph, so I can't wait to get it sorted, just waiting for the weather to warm up a bit first :wink:

 

[djdex]

They are - especially if you hit sport mode first, the acceleration is incredible and it just doesn't run out of steam like every other car I've driven does, it keeps accelerating until you bottle it or have to lift off because you're out of road!