Hello my 99 XJ8 is giving the following error codes P0304 Cylinder 4 Misfire detected, P1316 Injector circuit\IDM codes detected and PO354-Ignition coil D
primary secondary circuit malfunction. My question is how do I determine which is cylinder 4, Coil D. My second question is would an injector stop firing if the coil is bad?

Thanks in advance

 

No, an injector should keep working. Do a search on here, I recently saw a thread on cylinder numbering for the XJ8.