How difficult is it to replace the spark plugs and ignition coils on a Jaguar S type 4.2 2003

 

Remember to post an introduction in the New Member Area.

Changing the coil units and spark plugs is not difficult, but due to the age of the vehicle, it may be also a good idea to replace the cam cover gaskets, spark plug boss seals and VVT seals as well.

 

Welcome to the forums John,

I've moved your question from General Tech Help to S-Type forum. Members here with the same model will be able to help.

Graham

 

Just a word to the wise: It is best to stick with OEM brand coil-packs, e.g., Denso, Dephi, NGK, etc. Bargain, no-name parts from eBay and the like have caused many, many headaches for forum members over the years.

 

The 4.2NA looks better plug access than the STR (where the rearmost are awkward). I found taking them out much easier with hot engine.

The correct plugs already have anti-seize on them and are pre-gapped. If you still wish to check the gap be very gentle as the electrode tip is meant to be very sharp and you could damage it thereby ruining the plug.