hello. This is my first post so bear with me. I got my 02 liberty for free from an uncles friend. It started having problems one cold -45 Celsius day. It has codes for all cylinders misfiring and one multiple cylinder misfire. Also has codes for 02 sensors , thermostat sensor and so on. It bogs out at 3000rpm and can only accelerate super slow. Also has the loudest knock I’ve ever heard. I just found today that it has a fuel leak right where the fuel line connects to the fuel rail. I’m not a mechanic by any means. So basically I’m wondering if the fuel leak could’ve caused all this mayhem or is my engine on it’s way to a pick-a-part. Thanks guys.

 

the fuel leak could very well be causing most or all of the issues. modern fuel injected engines are reliant on the fuel pressure being correct or the computer is unable to compensate for changing conditions. The knock could be anything from really bad to nothing to worry about, a friend of mine has a 3.7 that developed a knock, I went around the motor with a stethyscope to find to my surprise it was a fuel injector. Fix the fuel leak, clear the codes and see what happens.