96 F150 4.9L cylinder head check leaking out of exhaust valve's

This 4.9l engine had a bad head you can hear it leaking out of the exhaust valve and here are the steps we took to find out what was going on with this 96 F150. Truck has p0171 code and 2 mechanics couldn't find the issue. Amazon Affiliate Links https://amzn.to/3Qg6NnH (budget suction gun) https://amzn.to/3xqd8V2 (block tester) https://amzn.to/3txez2E (block test fluid) https://amzn.to/3zD9YzK (compression tester) https://amzn.to/3mR92Al (leak down tester) https://amzn.to/39aCApd (brake clean) https://amzn.to/3MA9hKg (red cotton shop towels) https://amzn.to/3H6aUyq (blue paper shop towels) https://amzn.to/3mzrxcg (budget screw driver set) https://amzn.to/3xE06Vf (budget tool set) https://amzn.to/3Hosu0V (budget mechanics tool set) As an Amazon Associate I earn a small commission from qualifying purchases.