Engine Soon Light

http://Toyota.autoboardz.com/dreaded-Service-Engine-message-ftopict210236.html (dreaded Service Engine Soon message)
ok, so I just got my 2003 325ci, and the Service Engine Soon light comes on....browsing back through old threads, I see a commom culprit is a loose gas cap. Someone had mentioned that you must hear 2 clicks before the gas cap is completely sealed and tight and wait a few days for the light to go a..
« The loose gas cap is merely one of a whole laundry list of causes. It is just the cheapest and easiest to fix. Another reason is a bad O2 sensor. Those things get hot. But you need to get the cod.. »
« Go to AutoZone, they will give you a readout and give you a few remedies. I was getting a code for a faulty O2 sensor. One of their remedies was check connector, Bingo!!! Reconnected front sensor le.. »
« took it to a mechanic who did a computer readout of the code....computer says its a thermostat problem. Thermostat seems to level off at the halfway mark on the dash console. however after doing to .. »
« I had my thermostat replaced on my 2002 325CI at around 30,000 miles! Joe »

http://Toyota.autoboardz.com/bought-Sentra-2001-8L-ftopict210693.html (Just bought a Sentra 2001 1.8L and...)
After I filled up the car for the first time the service engine soon light came on.(as is, where is kind of sale) Car is working normally with no loss of power. Is there a way to read the code or codes without a proper reader? Key, foot thingy! I have found plenty of website with the meaning of ..
« If there is an Autozone parts store around, they will read the code for free. Maybe some other parts places in your area will read them for free too. Ask around. The code won't necessarily tell y.. »
« It may be you didn't put the cas cover back on tight enough, a similar thing happened to me, and I didn't figure it out until I put gas in the next time and realized the cap was ever so slightly not.. »
« Or you left it running while filling up. »

http://Toyota.autoboardz.com/Chevy-Tracker-Problems-ftopict222902.html (Chevy Tracker Problems)
2000 Chevy Tracker 4dr 4x4 service engine soon light came on and stays on.

http://Toyota.autoboardz.com/SERVICE-ENGINE-LIGHT-ftopict224756.html (SERVICE ENGINE SOON LIGHT)
2000 saturn sl2, just serviced replaced entire radiator, now my service engine soon light is on what could cause this

http://Toyota.autoboardz.com/97-Plymouth-Grand-Voyager-SE-Problem-ftopict230411.html (97 Plymouth Grand Voyager SE Problem)
Hello. I have a 97 Plymouth Grand Voyager SE with 197,000 miles. Recently the service engine soon light started coming on and the van started stalling at idle. I took it to a dealer and they couldnt find anything wrong with it except Map Sensor/ Baro which I already had replaced. I also had it at ..
« Your gonna have to perform the diagnostic test procedure on the map sensor circuit. If you are loosing the 5volt supply, or ground or the sense wire has a problem it will turn on the lite. A bad PCM.. »
« ... Sometimes it is not the map sensor itself but the connector to the sensor. There are 3 wires to the plug and one might defect due to the vibration or rusted even. Get a second hand one for abo.. »
« Shooting from the hip I'd say vacuum line leak or throttle body needs cleaning. But there's lots that can go wrong with an engine with that kind of mileage. You need to get someone who can give it.. »

http://Toyota.autoboardz.com/92-buick-headache-ftopict249735.html (92 buick headache)
My 92 buick lesabre will start if the SERVICE ENGINE SOON light is on when key is turned on. If light is not on when key is turned on it will not start. anyone have an idea?
« I would suspect a bad ignition switch. »
« If the SES is not on, PCM may not have woken up. No PCM, no fuel. »