Just found this problem, engine light on showed a misfire. Had shop
double check all of the injectors and fuel pressure, all good. Install

a new fuel filter. Then did a new plugs. Thought it might be a spark
plug wire, installed a know good one, no fix. Then swapped with the
one next to it, still no fix. Replace coil, no fix. Replaced the ICM,
no fix.
Thought this could be related to the plenum problem noted here, not the
issue, the engine is not using any anti-freeze.
Tonight, I listened to all of the fuel injectors, all sound good.

Can a timing chain cause this kind of issue? It has never been
replaced on this car and it has 165k miles on it. However, why just #4
misfire. Overall, the engine runs great at highter speeds, only
misfires at idle.