2004 CTT with misfire, faults P0300, P0304, P0307
 

Car has a new "knock?" or dull rumble that seems to come from the top back passenger side of the engine. Car seem to run/idle fine. I have not done any troubleshooting yet. Just stopped driving it. Any ideas before I start tearing into it??

http://forums.pelicanparts.com/uploa...1616437103.JPG

Here's hoping it's coil packs.

The dull rumble doesn't sound good. OTOH, I doubt you would get misfires detected from a lack of air/fuel. I maybe wrong on that. My expectation is that the system only checks electrical... current and voltage, and not whether a proper burn was completed.

Thanks. I got the cover off the passenger side, but that is as far as I have gone (as I ran out of time). No obvious visible damage to any of the coil packs (which are likely original). The noise (before I removed the cover)...sounded like valve train...maybe a lifter or valve timing is off...but just guessing. Hopefully coil pack. Not really sure how to troubleshoot other than check the sparkplugs for fouling or swap the coil pack out for the indicated cylinder...maybe check the fuel injectors.

I keep a spare coil or two on hand. While you may see (or not) cracks on the CP (coil pack) body this does not indicate if they are any good or not.

Pulling the plugs shouldn't hurt. The CP's could be struggling if the gaps have grown too large.