Started missing badly. Starts, runs poorly. Code says #1,2,3,4 cylinders misfiring. Nothing obvious.

 

Ouch. The timing chain has most likely jumped. You did not believe the warnings?

 

+1 IT IS VERY OBVIOUS, YOUR TIMING HAS JUMPED ON THE RIGHT BANK. Don't drive it; don't start it. On the right side (your codes are all right side): Pull the air box off; remove the air tube from the throttle body and connectors. Remove the cover to coils; remove the coils and harness (carefully); pull the plugs; remove the cam cover, be careful of the gaskets and seals, you will want to reuse them. Does the car have red or orange secondary tensioners? If so, order the replacement kit from Christopher Car Parts or your neighborhood Lincoln dealer. Search for secondary tensioners on this sight and Google (YouTube), read all, memorize everything OR HAVE IT TRUCKED TO YOUR FAVORITE INDY.

Reasonably easy repair if you are handy with tools and have a decent toolbox. There is satisfaction in doing the job yourself but lots of pitfalls.

Now, two years ago, a gent on the XKR forum had the same issue; we all jumped on the secondary timing: wound up he had dirty coils . . . but I wouldn't bet on it.

 

Thanks. I followed several threads and concluded the same thing. I replaced the chains in my 66 e-type, so am not a stranger to the issue. Most folks indicated to replace the chains at the same time as the tensioners. I can't remember if they are plastic or not. I would think replacing them, which is a bigger job, would be a good idea.

 

Generally, the chains do not need to be replaced, only the tensioners. However, in the case that the chain has jumped a tooth, I would change the chain and check the sprockets carefully.

With luck, you have not crashed the valves and pistons.