Service Engine Soon Light

[britishf-bird]

Okay this may sound stupid but I figured ill ask anyway.

Now obviously this light comes on to get the car serviced, but would this light come on for other than a general service.

Maybe there is a problem that I do not see, hear, feel with the engine and the light has come on to tell me this?

Any insight on why the light may come on other than a general check up.

Is there anyway to turn it off, b/c I doubt I will go and get the car serviced unless there is a bigger problem that I do not see?

Thanks!!

[ConElite]

The light does not come on for General Service like the Change oil light. The SES light comes on when there is something wrong in the engine and needs to be checked. Check your gas cap, Once in a great while its that but I Would recommend you get it checked out.

P.s. a sig. would help us in knowing what Make and model and year your talking about.

[BrdWAtti2d]

Just to add to what a was already said. It's not necessarily a reason to freak out. I've found that these cars will pop random SES codes that never reappear. You can buy an inexpensive scanner which will read the codes and reset the light. Just be sure it matches the specs for your car, which as ConElite pointed out, we have no clue what it is.

[britishf-bird]

Thanks guys!

Sorry about that I will put it in my sig as soon as the userCP comes back up.

For now:

99 Firebird
v6 3.8L
5MT



I do have a coolant problem, I have to top it off with water often b/c I have a leak somewhere, and I have not had the time to check it out. B/c I have been at school and there is no trust worthy place down there.

All responses will be taken into consideration THANKS!

[Injuneer]

The "UserCP" is permanently "down". Use the "QuickLinks" button to reach the signature screen.

[smanx57]

My SES light is on on my 1997 Trans Am. I have a purge problem, charcoal cannister is bad (I'm told). I will be replacing it soon along with the selonoid. If you disconnect your battery the light should go off for a while, buut will eventually comr back on. Aamco checks engine lights feree of charge and will tell you whatthe problem is.

[dogbone]

Try disconnecting your battery + side for about 5 minutes and reconnect it, it sometimes resets the light.

[britishf-bird]

ok will do!

smanx57:
what is charcoal cannister???

[Injuneer]

For the OP... there are OBD-II code readers available in the US for less than US$50. Worth getting if you intend to drive an OBD-II vehicle for any extended period of time.


For smnx57 - What is the EXACT code you have for the EVAP system? There are three different codes for the system, and knowing the specific code you have will help tell specifically where the problem is.

The EVAP system consists of a small (~8" diameter x 6" tall) plastic canister in the drivers rear fender, filled with charcoal particles. The vapor/air mixture that vents from the gas tank passes through the charcoal, and the charcoal absorbs the fuel (HC) vapors. Then the PCM opens a "purge" solenoid on a bracket on the passenger side of the intanke manifold, and engine vacuum pulls air through the canister, picking op the fuel vapor and burns it in the engine. The vacuum source is a connection on the passenger side of the throttle body. On the OBD-II cars, there is a vacuum switch in the line from the canister to the purge solenoid, to determine when there is vacuum in the line.

On OBD-II cars, one code indicates the electrical circuit to the purge solenoid is faulty. One code indicates the solenoid is stuck open, and not allowing vacuum to reach the vacuum switch (or the vacuum switch is faulty) and the third code indicates the purge solenoid is stuck open (or the two hoses are connected to the wrong nipples on the purge solenoid), and there is a vacuum on the line to the tank when there isn't supposed to be.

To clear a code, simple pull the "PCM BAT" fuse for 30 seconds. No need to disconnect your battery - that will just trip the audio system security, and you may have forgotten the code. And no need to disconnect anything for 5 minutes.

The code will clear, but if you haven't fixed the problem, when the vehicle is operated at the specific conditions required for the PCM to run the diagnostic routine for that problem, the code will be set again and the SES light will come on. Once the SES light comes on, the code is stored in the PCM for a failry long period, so it pays to scan it for codes even after the SES light goes out. I have not seen a lot of instances of "random" meaningless SES lights popping up in these cars. If the light comes on, get it scanned, and if someone scans it for you, write down the EXACT code, so we can help you determine the possible causes.