[Subscribe to Daily Digest] |
![]() | [Main General Bulletin Board | BBFAQ |
Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
R/R Mechanic Posted by Ari [Email] ![]() ![]() In Reply to: 9.5 check engine light, wm grimes, Mon, 16 Oct 2006 14:49:46 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The 9-5, like any car built after about '96 has extensive built-in diagnostics. Any time the CEL comes on, a fault will be written into the computer's memory. And it will stay there until read out/cleared, even if you disconnect the battery.
And a mechanic with the proper tools can easily read out the codes. Heck, you can drive down to the local AutoZone or the like and they will read out the codes for free. The code(s) is(are) only a starting point - if the code says the front O2 sensor is out of range, it could mean that you have a vacuum leak or are running too rich.
The engine can run just fine and you can pass all smog checks, and there still be something wrong. Not badly wrong, but wrong. The engine control system can adapt to lots of minor problems. But since the system CAN adapt to problems, how would you know to fix them? The CEL. So if a sensor or reading goes out of tolerance for a little bit, the CEL will come on.
If I had to guess, the problem is with the Vapor recovery system. This is the system that all newer cars have which capture fumes from the gas tank in a charcoal canister, and burn them at the proper time. In the olden days, gas tanks were vented to the air, and gas fumes contribute to air pollution. In order for this system to work, the fuel system is sealed. To tell if the system is sealed, the engine control does some tricky things with vacuum and expected pressures. If something is a little amiss, it will light the CEL.
The first thing I'd do is buy a new gas cap. They're not expensive. A slightly leaky gas cap will screw up the system. It isn't leaking fuel, but the gasket gets worn and air gets by. The problem would show up most if the car has been driven for a while, or the tank is near empty.
If that fixes it, cool. If not, get the codes read out and go from there.
After that, I'd find a new mechanic. If the mechanic hasn't read out the fault codes, he isn't doing his job. If he is reading out the codes and done nothing, I'd still replace him. If a hired professional - mechanic, plumber, neurosurgeon - says he/she/it doesn't know what's going on, I'll believe them, and then find someone who does.
If the mechanic has read out the codes and done a bunch of troubleshooting and is still stumped, I'll give them the benefit of the doubt. But I'd want to know what the codes are, and what troubleshooting has been done.
posted by 192.249....
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |