Car savvy folks? Car question for ya!

I don't  have any advice for you except that I've learned when that little light comes on, it's best to get it checked out by someone who knows what they're doing and then let them turn it back off.
 
Joyce

I'm bringing it into the shop on Thursday.  Just wanted to check and see for opinions so that I have an idea of what to talk about with the mechanic!  []

i'm not positive on this, but it could have something to do with your fuel filter. i will ask dh when he gets back from the store, his dad is a master mechanic and he worked for him for years, so he is pretty knowledgeable about that stuff.

Thanks!!!
 
My fuel filter is probably due. 

Make sure your gas cap is on tight.  Ours went on, when DH took it in it cost him $60 for them to check it out and tell him that his $3.00 gas cap needed to be replaced.  If it isn't on tight, screw it on tight, or get a new one.  Give it a couple of days and it should turn back off.   If it doesn't than it could be something else. 
 
[link>http://forum.dog.com/asp/showProfile.asp?memid=19346]Xerxes[/link] is really good at this kind of stuff.  Maybe he will stop by and give you some ideas!

Make sure your gas cap is on tight.

 
I was thinking this same thing.  My DH drives a Chevy Blazer and the "check engine" light comes on periodically, but if he fiddles with the gas cap, it goes off.  It's certainly worth a try.

The gas cap thing happened with my Toyota Corolla once as well.

If you take your vehicle to Autozone, they'll plug a code reader to your car, and they can tell you exactly why the check engine light is on. They should do it for free - it's a much cheaper option than a mechanic.

Gina...you might want to pm Xerxes...he works as a lead in the parts dept for a huge car dealership and repair shops. He also spent many years helping his grandpa who was a mechanic...so needless to say he knows a LOT about cars and he won't mind you pming him with questions.[8D]

I will also let him know to visit this thread and see if he can offer advice.   []

The check engine light is telling you that your O2 sensors are reading too much or too little of something in the exhaust.  Perhaps you are running too rich, or perhaps too lean (too much fuel or too little fuel in the mixture.) 

The first thing to look at is your air filter.  How long ago was it changed?  Pull it out and look at it.  If it is dirty to look at, replace it.  If it's been more than 30K since you changed it, replace it. 

Secondly you may want to run a good fuel injection cleaner through your fuel system.  Something like a BG 44K, or Techron or even better get a induction service done.  The induction service will clean out the air passageways of some of the carbon that is inthere.  Most of it actually. 

Have you noticed a lack of power?  Rough Idle?  Anything of that nature?

Unfortunately the check engine light is just an indicator that something is wrong.  And it takes a mechanic shop with the appropriate tools (not just a code reader)  but a tool that actually reads the data stream to tell him what's actually happening inside that engine.  The data stream will tell you and the mechanic EVERYTHING that's going on in the engine. (fuel injector duration, spark voltage, coil firing times.  Also putting your car on the emissions inspection machine will tell the tech whether the engine is running lean or rich.

I don't know what labor rates are in your area, but if you PM me with your VIN and other info I will tell you parts prices on things like O2 sensors and various filters.

sorry i took so long to get back, he said the most common cause is a loose oxygen sensor.

Modern cars have fuel injection systems with a pressurized fuel delivery system. If there is a leak or the gas cap is not on properly, the system can't build the proper pressure and the light comes on. Going through that much gas might be a fuel leak somewhere. Either case, you're definitely looking at a garage visit.
 

Wow, thank you guys so much!  I really appreciate all the responses.  It's definitely not the gas cap issue (darn, that would have been a nice quick fix!!)  Xerxes, thanks for your post!
 

ORIGINAL: Xerxes

The check engine light is telling you that your O2 sensors are reading too much or too little of something in the exhaust.  Perhaps you are running too rich, or perhaps too lean (too much fuel or too little fuel in the mixture.) 

The first thing to look at is your air filter.  How long ago was it changed?  Pull it out and look at it.  If it is dirty to look at, replace it.  If it's been more than 30K since you changed it, replace it. 

Secondly you may want to run a good fuel injection cleaner through your fuel system.  Something like a BG 44K, or Techron or even better get a induction service done.  The induction service will clean out the air passageways of some of the carbon that is inthere.  Most of it actually. 

Have you noticed a lack of power?  Rough Idle?  Anything of that nature?

Unfortunately the check engine light is just an indicator that something is wrong.  And it takes a mechanic shop with the appropriate tools (not just a code reader)  but a tool that actually reads the data stream to tell him what's actually happening inside that engine.  The data stream will tell you and the mechanic EVERYTHING that's going on in the engine. (fuel injector duration, spark voltage, coil firing times.  Also putting your car on the emissions inspection machine will tell the tech whether the engine is running lean or rich.

I don't know what labor rates are in your area, but if you PM me with your VIN and other info I will tell you parts prices on things like O2 sensors and various filters.

 
I just had my oil changed last week, and they checked the air filter and showed it to me: it wasn't too bad.  The shop recommended that we just change it next time. 
 
I haven't tried the fuel injector cleaner.
 
I have noticed no lack of power, no rough idle, nothing wrong or different whatsoever with the way the car runs.
 
I'm hoping it's just a loose sensor.  About 8 months ago when my spark plugs were changed, my check engine light came on the next day, and they said it was a sensor that must have been knocked loose when they were getting at the plugs.  Hopefully it's the same thing. 
 
Luckily, my mechanic doesn't charge for diagnostic work if he finds the problem and fixes it.  I'd just have to pay for parts and labor. 
 
Thanks again!!!  I really appreciate it.  Car goes in tomorrow.

a sensor

 
I've replaced an O2 sensor twice. They go bad. Xerxes is right, they determine how rich or lean your fuel is running.