my 90 deville has been a pain since I bought it used. Sputters, backfires,
won't go more then a few miles an hour. only does this when it wants to.
Worse when AC is on or other electronic devices are working. Have had all
major systems checked. its been tuned to the hilt. When its not doing its
crazy thing, computer checks come up negative.Service engine soon light
has been on for all of the time i've owned it except for about the first
few days after tune up
