Check Engine Light Issue - how worried should I be?

[Yelena]

Hi everyone,

This is my first time posting here, but it looks like a really helpful place. Here is the story:

I have a 96 Camry LE that I recieved after my uncle passed away in March. The car had absolutely no issues with it that I know of, other than a need to replace the serpentine belts, which I will be getting taken care of in the next two weeks.

I got an oil change done this past Friday, and other than the serpentine belts, there were no issues. While driving on Saturday, my check engine light came on. I assumed it might have something to do with the oil change, such as a sensor left unplugged or something minor, and called the company. They had me bring it in tonight to take a look.

When I brought it in tonight, I asked what the mechanics would do. The sales guy said they would check to see if the issue was from them and fix it. Otherwise, they'd have to run a hookup code test, and that would cost me $129. Of course I don't want to pay that, knowing they can diagnose it for free at an Auto Zone. So I explicitly said to check for oil-change related issues, but otherwise I will have it looked at elsewhere.

Well, the car was checked over, and while the mechanic said it had nothing to do with the oil change, he turned the freaking check engine light off! I was very frustrated, since now there is no way that I know of to look up the code on the problem. I debated for a bit with the sales guy and eventually he told me to call the manager in the morning. I doubt I'll be getting the code out of him with no charge, and it makes me furious that now I can't bring it to an auto zone. I drove the car home (about a 10 minute drive) and the light has no come back on. Also, I've been driving it with the light on through Sunday and today, and the car sounds fine. No different than usual.

So my question is, other than calling the auto shop and complaining, is there anything else I can do to figure out the problem? My best guess is that the oxygen sensor is old, since the same thing started happening around this age mark with two Corollas my parents own. The problem is, I am going on a 4,000 road trip in a week and a half, and would like to find out the problem and fix it by then. If my check engine light doesn't come back on by then, is there anything at all I can do? Also, is there anything else it could possibly be?

Thanks for any help and suggestions you might have!

[RIP]

And the mech thought he was doing you a favor. Hope he learned something. They likely reset the light by pulling a fuse which erases the code from the memory. It's gone. What to do? Drive the **** out of it for a few days and see what happens. Try to duplicate throttle settings and shift patterns you were at when the light came on. Keep in mind some error codes only produce a check engine light if it fails twice on seperate trips ie, 2 trip logic faults. You'll have to start, drive, turn off, start, drive to get the light to light.

Since you didn't see any associated driveability issues when you had the light, my guess (that's all it is) is it could have been EVAP system related. This system traps gas fumes when the engine is off, then recirculates them to the engine when it's running. You usually won't notice anything but the light. Could have been an O2 sensor heater going. Sometimes all you'll see is the light. Just about any other sensor failure will give you a light and additional issues. Not a good idea but, I've read about guys driving for years with CE lights on.

Oh ya! Welcome to the forum!!!!

A loose gas cap can generate a CE light.

[Yelena]

Thanks so much for the quick reply. Yes, that's my guess also, because as I mentioned, the same thing started happening with my parents' Corollas around this time, and it turned out to be the Oxygen/emissions situatuion, and they just simply needed to replace the oxygen sensor.

I wouldn't be so worried about it if it wasn't for the 4,000 mile road trip coming up very soon, and I don't know if I want to drive the shit out of my car until then to hope the light comes back on. (Although it's a great and practical idea - I might just take a trip across the border into WI and see if that does the trick).

I will call the manager of the auto shop tomorrow and complain about the situation. Do you think that they would have saved the code reading (I saw them do it)? I'm hoping if they did, the manager will tell me what it is at no charge for their mistake. If not though, I guess I'll just hope for the best.

[snowskateskim21]

best thing to do is the see if it stays off...it most likely is not something to worry about unless you hear an unusual noise or notice a difference driving. The best advice I can give you is if it does not come back on then you really don't have a major problem. Don't worry about it.

[Yelena]

Yeah, I'm sure it's not a problem if it stays off. What do you recommend I do though, if it goes on again during the road trip? (MN to New Orleans and various places around FL)

When I was driving the Corolla and the check engine light issue started happening, it would go on every couple hundred miles, and the issue turned out to be the oxygen sensor. If this follows the same pattern and keeps running fine, should I assume that's what it is?

Thanks!

by the way, when the corolla light came on, I manually turned it off. If I can do the same thing with the camry, is it safe?

[snowskateskim21]

When it comes to that light it is impossible to track down what the problem is without a diagnostic because of today's technology in cars. Since they run on computers then there could be numerous problems. But if it does not come back on for a few days you will be fine for your trip.

[RIP]

Originally Posted by Yelena

Well, the car was checked over, and while the mechanic said it had nothing to do with the oil change,

This inferes, they may have found the cause. Ask.

They may or may not remember the code. As snow... infered, don't loose any sleep over it. If it doesn't come on in the next few days, don't worry about it.

[Yelena]

Thanks to both of you. I believe they did find the cause, but are not telling me because I need to pay the $129 to find out. I will talk to the manager about that in the morning, and we will see what he does. Otherwise, I won't worry anymore.

[xfeejayx]

I would also recommend getting a new mechanic. $129 for a diagnostic is ridiculous. Most places I've seen charge about $89, The place I go to now doesn't charge at all. And it seems you don't trust them either.

[Yelena]

Yes, I definitely will be from now on.

It's more of an auto center where I go to get an oil change every $3000 miles or so, but I always get repairs done with a family friend. All I wanted them to do was to check and see if they unplugged anything during the oil change, not turn off the light that indicates there's a problem. :/ After I talk to the manager today, I will not be going back there either way.

[dosser]

For the small investment of about 100 bucks you can buy your own code reader and read your own codes anytime they appear. Mine has saved me the time and trouble of taking the vehicles somewhere to find out the problem. Dosser

[Yelena]

Where would be the best place to buy one of those at that price? I've been looking around the web and have been seeing them for around $200.

[dosser]

I live in Washington state, got mine at a store called Schucks.
Bought it on sale for $98. Dosser

[JOET/CAMRY]

Originally Posted by Yelena

Where would be the best place to buy one of those at that price? I've been looking around the web and have been seeing them for around $200.

You might want to check Walmart. I have seen 2 different models there. I'm not quite sure of the price but they should be fairly cheap. Well, as far as price is concerned. Take care.

Regards,
JOET/CAMRY

[rimfire,22]

Yelena,

You didn't mention if you took it to a private mechanic or dealership. If it was private I'd be careful in the future. They may have done it purpose to get you to come back and spend more money!!! If it was a dealership then they would look it over and maybe reset the light for you for no charge what so ever. My opinion only.

rimfire,22