One problem related to power train has been reported for the 2004 Cadillac Deville. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Cadillac Deville based on all problems reported for the 2004 Deville.
Main computer failed while driving causing total loss of power. One pin was bad in the computer that controls the cars fuel, engine, etc. Replaced the defective computer costing over $1,000. Prior to the failure the check engine light came on many times. The computer did not store a code for this problem. This total loss of power is a costly safety issue.