A few days back my 2004 XJ8 upon starting shook for a few seconds and shut itself down. I restarted the car a few seconds later and it drove fine but with a check engine light on. When I got back home I hooked it up to a scanner tool and it revealed a P0300, P0301, P0303, P0305 and P1316 error codes. All of them relating to cylinder (1,3,5) misfires etc. Since I reset the codes I haven't had any problems yet. I once had a similar problem a year or so ago but it never came back until now. The one change to the car has been that I had a new throttle body installed about 6 months ago.
The car drives fine but I wanted to know if this is a precursor to something major coming down the road. The car has 130k miles and I have had it since 2004 as new.
Any feedback is appreciated. I am also attaching the DTC view from the diagnostic software for the experts to decipher what is wrong.

 

Seems to be a coil or coils to me?

 

Add a bottle of BG44K to the fuel and see what takes place.

 

coils need to be replace. I concur.

 

When the coils fail they fail when you have the indication that three coils fail at one time and the car codes reset and it runs fine for now you do not replace the coils. For now I would hold off on replacing the coils add the fuel additive and see what takes place. This could be a spark plug or fuel issue not a coil.

 

Listen to Gus...... he's steering you down the right path.

What you describe is way too random to attribute it to ignition coils at this point. Locate some BG 44K and get two cans. Add one to a full tank, then wait and add the second to the third or fourth tank after that. Between that and the coming return to summer blend fuel, you may not have any further issues.

Good luck!

 

Thanks everyone. I put a can of BG44k after fillip today. I have another can that I am considering using for the third fill-up as xjrguy suggested unless anyone objects. On this 20 gallon tank and my limited driving I will probably get to it in about 3 weeks I think.

 

Was this ever resolved?

 

Also curious if this was resolved

 

It is hard to say but if it did not it might have been spark plugs we will never know. Your best bet if you have a problem is to start with a good fuel conditioner like BG44K and see how it goes.