E-93 Cranks But Won't Start - Tech Tip:
Had a 2008 328i (28,000 miles) come in with a crank but no start condition. The dealer had checked everything and came up empty handed. I discovered the problem was a loose ground behind the upper half of the rear passenger's seat. I applied dielectric grease and tightened the 6mm nut (10mm hex) and the car fired right up.
Hope this helps...
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