Welcome,
Please go to your control panel and enter some info about your car.. make model engine number of miles. This way when you ask a question we'll have a little something to go by and we can be more specific in our responses.
Consider doing an actual compression check, if that cylinder is relatively low, then add a table spoon of oil into the cyl and recheck. IF the compression goes up it is the rings, if not, its the valves.
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BroncoJoe19
2006 Alt Fuel Jeep (electric)
'98 windstar 3.8L
'99 Crown Vic 4.6L
'90 Full Size Bronco 5.0L
I'm not a professional mechanic, take my suggestions with a grain of salt, or a cup of coffee  If you found this post helpful, please click this  on the left of this post.
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