Date: Thu, 26 Dec 2002 10:01:20 -0500 From: "Kenneth S." <nimrodnopsams.com> Subject: Re: CHECK ENGINE light on
MikeYankee wrote: > > This has recently happened to me, too. 1995 900S with 90k miles, running fine > and well maintained. > > It's only happened twice. Both times while powered back on a long downhill. > The first time, the light stayed on; pulled off and restarted the car -- no > light. The second time, it was on for a few seconds and went off by itself. > > Before I spend $$$ replacing the oxygen sensor or chasing down a wiring > problem, I'd be interested to hear what some of this newsgroup's experts say. > > Mike Yankee > > (Address is munged to thwart spammers. > To reply, delete everything after "com".) I have had this problem with my 1996 900SE. However, in my case the check engine light came on and stayed on. There appeared to be no reason for its coming on, and there was no change in the driveability of the car. I won't go into all the twists and turns that went into trying to diagnose the problem. In brief, in the first round, the dealer said the problem was cured after several visits, culminating in the resoldering of a wiring harness. The problem stayed away for more than a year. In the second round, about a month ago, an independent Saab mechanic said it was likely that there was something wrong with the gas cap. I agreed to get a new gas cap, but I am not convinced that this is a permanent cure. (We went through the changing the oxygen sensor bit last year, but the light came back on after a relatively short time.) My understanding is that the check engine light essentially monitors the operation of the emissions-control system. If yours comes on only momentarily, and then goes out again, if I were in your shoes I'd leave well enough alone. Treat it as a Saab attention-getting device.