1998 XJR - I'm getting Restricted Performance warnings, from a cylinder 1 misfire (P 0301).

So far I've just replaced the spark plug, and the warning came back. One thing I'm thinking is this: where the coil wire harness plugs into the coil on cylinder #1, there is no "click" because the plastic latch inside it is broken. I push it in as far as it can go in, and it appears to be pushed in just as far as the other coils, however, no click. I'm thinking (and hoping) that this is more than just a coincidence - that a bad, or no wire-coil connection may be causing the misfire. Does this sound reasonable, even though it's pushed into the connector just as far as the other coils?

If this is the problem, anyone have any ideas how to fix it, short of buying a new coil wire harness for the A bank?

Thanks all!

 

glue? .. cylicone? tie strap

 

There is no harness just for that bank. It is part of engine harness. As Genius said, silicone or similar. If code reappears you may have bad coil.

 

I'll try silicone....but just wondering, if the cylinder was misfiring because of a bad coil, or a bad coil connection, wouldn't a coil OBD code come up as well? The only code was the p0301 and p1316(misfiring affecting emissions). Perhaps not, just wondering.
Thanks again,

 

The ECM knows it is firing the coil, so wouldn't set that code. It can sense the misfire based on he engine speed sensed by the crankshaft position sensor. Misfire code is about all you will get unless coil is shorted. At that time ECM knows it cannot fire coil and will flag appropriate code for coil.