Service Engine Soon Light

[Batboy]

My stinking light came on. Car runs fine. Any ideas on how to debug for a do-it-yourselfer? Does this light come on when it's time to change oil? And how do I reset? If there are methods out there maybe we should post those on the "how-to" page. I couldn't find anything in there on this. Thanks in advance!

 

[94RT10Ohio]

No, it is not your oil.... You need to have the car scanned to get the code, then go from there. Disconnecting the battery will reset, but better yet it can be cleared with the same tool you use to scan to get the code.

 

[Batboy]

So, the next question is if this tool is one of those ODB II or whatever they are called readers that cost like $3K? And that begs the question do I then need to take it to a tech? I've heard sometimes the light will come on for an O2 sensor or something that is only temporary, and to try reseting to see if it comes back on. If disconnecting the battery will reset I think I'll try that first before sending to a tech just in case it is something minor. Any other ideas out there let me know. Thanks!

 

[94RT10Ohio]

Generally speaking if a O2 sensor tossed a code it is not temporary, the sensor is going or is bad. There are many scanners available. From $50 cheap things that are hard to use and figure out what it means to crazy expensive stuff.

There are a few car parts places that will scan for free, although I would never take my Viper to one of those. I would trust a dealer to scan it. They usually charge a 50-75 diagnostic fee.

 

[Randy]

Generally speaking if a O2 sensor tossed a code it is not temporary, the sensor is going or is bad. There are many scanners available. From $50 cheap things that are hard to use and figure out what it means to crazy expensive stuff.

The little cheap OBD-II reader, sold by Harbor Freight or Roe Racing for less than $50, is simple to use, and gives you a code which you look up in the booklet it comes with. For any do-it-yourself'er, its a very useful tool. There is no guarantee it will help you fix it, as, indeed, some of the codes are too general and do require a more detailed (expensive) scan tool, such as found at a dealer or some of the private shops, but I wouldn't discount its usefulness completely.

Just as a simple example: I once made the mistake of starting my Viper with the air-cleaner housing off - and thus the sensor on the housing disconnected. That set a code that was not self-clearing, which was confirmed and cleared by the cheap scan tool. So, it is indeed useful, and worth the price. It does not mean it will be as useful in all situations, of course.

 

[Batboy]

Ahhh so, this tool can clear too? Excellent! I may have to get me one of these. Thanks! Good example too.

 

[Eric H]

Batboy, just go to autozone, have them pull the code, then post the code here and we can tell you what it is. Autozone has the tool and will do it for free.

Could be a loose gascap, make sure its tight, also just unhook the battery for about 30 seconds to clear it out, if it comes back.........diagnose the code

I got the tekmate tool on ebay for $100 came with the software and cable to hook to my laptop, works great and it gives you performance information also!

 

[tarfungo]

Batboy,

Don’t know if this will help, but I recently had my ‘check engine’ light come on while burning down the highway. All seemed fine, but I pulled over just to check. Couldn’t see anything, so I restarted and the light was gone. Took it in for service and it turned out to be an air pocket in my cooling system. Just needed to burp and all was fine again.

Cheers, Greg

 

[Batboy]

Greg, I did consider this. I was at the track racing it and had something similar happen. So, I thought this might also be the case. But after several stops and turning the engine off and on it still comes on. That's why I want to clear it. I went ahead and bought the cheap reader from Roe. If that doesn't help I'll try some of these other ideas. Thanks to all.