1989 Cadillac Deville- Service Engine Soon

First, check the gas cap to be sure it is present and tight. That light usually indicates something amiss with the emission controls. If your locality has mandatory emission tests, you will have to get it serviced. If not, it is probably "safe" to drive. I recommend a visit to a Caddy dealer for a general check-over. My guess $200-$300.

I own a '90 DeVille. The "Service Engine Soon" light has been on since the day I bought it six months ago. I have had no problems with the car. I also have a '87 Fleetwood. This car I have had for over two years. When I bought it the "Check Engine" light was on. I asked a friend about it (he owns and operates a repair garage), and he said "Oh that... My truck has that same light on in it. I put a piece of electrical tape over the light because it was annoying." OK, so maybe his advice was a little flip, but his point was that as long as the car was running OK you could just ignore the light. And BTW, the Fleetwood runs fine.

Steve 1987 Fleetwood Brougham 1990 Sedan DeVille