My check engine came on last night and stayed on during multiple restarts and also again this morning when I started it. I thought I was ready to bring to the dealer Monday morning but the light "magically" went off while driving today. Has anybody else had this happen?. What could cause this? And finally would there be a code stored that the dealer could check?

 

I have not had this happen with the GS 350, but I have on other vehicles.

I don't have the reason the CEL came on, but oftentimes it take 10 complete [engine] On/Off cycles (with some drive time) for the CEL to go out if the error was corrected on its own. Since the CEL went back Off, it was nothing serious or long-lasting, but I'm sure you are wondering why it came On in the first place. Sometimes when the CEL just temporarily comes On and eventually goes back Off again, the cause is something like the gas cap not being installed tight (click), the knock sensor from not using premium gasoline, or something similar.

I don't know if the (corrected/self-cleared) error code is stored, or not.

 

Very informative. Thank you. I thought about the gas issues but the cap was tight and I always use a premium gas and tank was almost full. But it still could have been a gas issue like water or moisture because weather Temp has been fluctuating to really cold with snow.

 

The fault will be stored and can be read by your dealer.

 

Thank you.

 

From the Car Pro Weekly Newsletter:

"CHECK ENGINE LIGHT---WHAT SHOULD YOU DO?


When your check engine light comes on, it is a signal that the onboard diagnostics system (or OBD II) has detected a malfunction in the vehicle's emissions, ignition or fuel systems.

It could be something as simple as a loose gas cap or something as severe as a faulty catalytic converter, so you shouldn't ignore it. All cars and light trucks have onboard diagnostics that are supposed to detect engine-related problems that affect the emissions control systems.

The check-engine light (typically a yellow or orange outline of an engine with the word "Check") should come on for a few seconds every time you start the engine with other warning lights. If it stays on, that means there is a problem.

If the check engine light is flashing, that usually indicates a misfire or other serious issue, and it should be dealt with quickly at an auto repair shop.

Ignoring a flashing light increases the chances of additional problems, including damaging an expensive catalytic converter (which costs more than $1,000 to replace on some cars).

If it isn't flashing, before rushing to an auto repair shop you should first tighten the gas cap because a loose cap can trigger a warning. See if the light goes off after several engine starts over the next day or so. Replacing a worn gas cap that doesn't fully seal may also solve the problem.

If that doesn't do the trick, an auto technician will need to diagnose the problem by electronically tapping into an OBD II connector under the dashboard to read diagnostic codes that will help isolate what caused the light to go on, such as a bad spark plug or oxygen sensor.

Even if your vehicle seems to be performing well and your mileage isn't dropping, it's a bad idea to just ignore a check-engine light. Something is wrong, and it's likely to get worse. In addition, if you live in an area where vehicles have to pass periodic emissions tests, an activated check-engine light usually means your vehicle will automatically fail."

 

 

That (last) post makes me remember one day when my mother asked me to come over and check her car because it wouldn't start. The battery wouldn't even turn the engine over. I told her, 'Your battery is gone.' And she responded; ' Oh dear, I wonder who would have taken it.'

 

Or by OReilly or AutoZone or almost any store for free

Or I got an app for my iPhone and a cable that plugs into the OBD2 port so I can read codes

And then Google the code to find out what it means

Don't have to go to the dealer to get info

 

The Carista app can read error codes too.

 

I had my 2013 do this intermittently then stay solid over the course of a few days. Finally got fed up, ran it up to the dealer, and they had it fixed in a few hours. Diagnosis? Mystery, but I think they quietly replaced the fuel cap. The service advisor said they get duds once in a while and due to emissions standards, a pressure change due to a faulty cap bleeding off pressure will throw the CEL light.

Anyway, since that visit I just had the next service light come on for my 15k service (which is a waste of 100 bucks if you ask me, just change your wipers and wave a magic wand at it, save money).

 

Why is there even a check engine light today anyway? Why not just tell me what the problem is? Like, hey you left the gas cap loose, the #5 cylinder spark plug is misfiring.

 

Technology!...........Technology, my man. We must have more technology so it can be read on the computer and they can make another $100.

 

During my BMW ownership days, a check engine light usually meant a loose gas cap.

When the warranty expired, a check engine light usually cost me $500+ including the mandatory $100 diagnosis fee.

That's why I'm here.

 

Excellent question!