What is causing the plug on top of the oil intake to be blown out and make it sound like a loud exhaust
Car initially was sputtering/misfiring and
like a valve seal ,short the plug on that cylinder it will be quiet at least
Are the valve covers leakin' and drippin' oil onto the exhaust manifold making this in effect a Smoke Factory?~
ummm, these appear to have threads....you mean to tell me the thing unscrewed itself...all the time? https://www.google.com/#q=2007+chrysler+pt+cruiser+oil+filler+cap
Sounds like a LOT of build up in that motor......under pressure...
Check exaust out put, the symptoms sound like a seriously restricted catalyst. If the exhaust can't go out the back where does it go? That's right the intake the pressure finds a weak spot and equals the barometric pressure thus the exaust sound. Disconnect exaust flange 2 13mm bolts they have a tab on the nut side. W exaust undone at manifold start and w brake set and all rev engine see if symptoms seem cured. You don't need to remove exhaust flange bolts completely as you need a lift to reinstall them if you take them out you'll see why. Let me know if that helps
What makes oil pour out of throttle body at an idle in 40 minutes?