2008 Grand Cherokee 4.7 Intermittent No Start Technical Question
 

Hello everyone, been doing some reading online and found lots of people having issues with the 4.7 not starting but none of them seem to be related to the issues I'm having.




2008 Grand Cherokee 4.7L limited. 182,xxx kms. Past month or so it will intermittently not start after driving short distances. Will sit there and crank until the battery dies, but won't fire. Recently had a tune up, cleaned throttle body, new plugs, didn't make a difference. Has spark, getting air, seems to be getting fuel because 90% of the time it runs fine at all throttle positions. It always starts first try of the day, but after short trips (ex. to the gas station down the street) once it's been shut off for 10-15 minutes it won't start. When it doesn't start, we let it sit for about 10 minutes then it starts but idles really rough and throws Lean Bank 1 and Lean codes. After a minute or so of rough running, it runs and drives fine and codes can be cleared with no issue.


Issue happens very intermittently (hasn't done it for 2 weeks now). Anyone experienced this before? Wondering if maybe fuel pump is intermittently not putting enough fuel pressure to the rail to start it when warm. Thanks in advance.