Need some help! I have a 99 Grand Cherokee that hangs in first gear when it gets below a quarter of a tank of gas. Also the check engine light is on. Any IDEAS.

Get a diagnostic check, one of your sensors could have gone bad...

Checked your fluid level? DNF-trans warm (15 mile run) eng running trans in neutral to get correct level. Hang up in 1st might also be the trans control telling you something's wrong. Try this website for TSB's...
http://www.wjjeeps.com/tsb.htm#2000 (http://www.wjjeeps.com/tsb.htm#2000)

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