2002 Liberty Injector issues

Littleneo81

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So I have this 2002 liberty with the 3.7 v6 and when I got it, it had a blown head gasket on the passenger bank of the engine and had been sitting for probably about a year. I tore into it and replaced the head gaskets and every gasket on it as i built my way back out. I put new vacuum hoses from the valve covers to the intake, new coils, new injectors, new ac compressor, new fuel filter, and new fuel pump. It now cranks and runs fine for the most part. When driving and the rpm's above 1k it runs great but maybe a little lacking on the power that it should have. When idling it sounds like **** and runs really rough. Its throwing P0175 & P0172 bank too rich on 1 and 2. Its also throwing P0201,2,3,4,5,6 all 6 injectors open circuit. I cant for the life of me figure out why this is happening and its giving me fits i have put quite a bit of money and time into this nice little jeep but I'm at a crossroads where I'm either going to have to cut my losses and give up on it or keep going. I would really love some input from you guys on what i should check. What would cause all 6 injectors to report open circuit but still run? I was reading that the banks too rich can be cause by the injector issue so I'm thinking that when i fix them that should fix everything I'm seeing. I can erase the codes and it takes a day or so for them to all come back. I have cleaned the connectors to the injectors with GC bath and that made no difference other than they are now clean. Please help!!!
 

LibertyTC

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Have you checked the fuel pressure readings? Key On reading is? Running psi is? Off for 20 minutes reading is?
Are you using the Correct spark plugs? NGK-ZFR6F-11G gap .040 inch. What are the compression test readings on all 6 cylinders?
Could there be bad wiring / connector or bad ground situation?
PCM gone bad?
In situations like this it may be best to consult with an automotive electrical specialist and check it over.
Here is the 2002 Factory service manual: http://www.colorado4wheel.com/manuals/Jeep/KJ/2002JeepKJServiceManual.pdf
 

Littleneo81

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I will check those things this evening after work and report back. I know i do have the correct spark plugs gapped correctly, but as far as the rest ill have to check all that, i did a compression test before and after the head gasket job but haven't looked at that since and i have probable put about 4k miles on it since, as of a month ago i was getting 15.9 mpg and its now dropping, its currently down to 15.1mpg.
 

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