Re: 3.7 misfire- no start
Interference means nothing if you have a failed valve spring, there is more ability for the valve to deviate from its specified path which could create a collision course itself. You may be just fine, If you have access to a compressor and a leakdown tester you can check cylinder integrity before any repairs are performed or attempted.
Furthermore the head does NOT need to come off to replace the valve spring, you can feed paracord or similar synthetic rope down the spark plug tube with the cylinder mid way down its compression stroke, then roll it over by hand till its snug and viola, OR you can use a leak down tester to pressureize the cylinder, then you just need a valve spring compressor tool, they make them where they hook onto the camshaft and have legs that set on the retainer, you lever it down and remove the keepers, reverse with a new spring and viola.
Pulling the head is WAY more work than is required at this point.