2006 Liberty cranks will not start when warm but OK when cold

Discussion in 'Just registered? Post here to introduce yourself!' started by RodMac, Jan 12, 2020.

  1. RodMac

    RodMac New Member

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    2006 Liberty cranks, starts, and runs perfectly when engine is cold.

    If you drive 10 miles and turn it off and wait 5 min it will crank and not start. Wait 10 more min. and it will start.

    I replaced just the fuel pump, not the entire assembly and it does the same thing.

    Engine Running fuel pressure is 50 psi
    Engine off, after running waiting 10 min., fuel pressure is 52 psi and gets a crank no start.

    I can get it to start 3 different ways when I get a crank no start with a warm engine:

    1) If I drain the fuel pressure from the fuel rail shredder valve the Liberty will start perfectly and run well.
    2) If I let it sit for 15 min. or more it will start.

    3) If I spray brake cleaner down the intake it will start.

    Anyone have any ideas or next steps with troubleshooting?
     
    Last edited: Jan 12, 2020
  2. Billwill

    Billwill Full Access Member

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    Usually the cam or crank sensor fails when hot. Sometimes will post a CEL for the failing part so you need to read out the CEL codes stored....most common failure is the Crank Sensor.

    Download the 2006 KJ-SM.pdf here....the bottom of the Index Page lists the CEL codes and tells you which page to go to for that code.

    Section 8W has the wiring diagrams.

    www.colorado4wheel.com/manuals/Jeep/KJ/
     
    Last edited: Jan 13, 2020
  3. RodMac

    RodMac New Member

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    Thanks Billwill. I’ll check it out.