service engine soon light

I just bought a 1999 GMC Denali firm a guy ib NY> I drove it back to KY without any problems. Yesterday the engine service light came on. How can I find out the problem code without going to a dealership and be charged$100.00?

Go to Autozone or another type of auto parts place. Autozone will check what fault codes are set for free.

I just bought a 1999 GMC Denali firm a guy ib NY> I drove it back to KY without any problems. Yesterday the engine service light came on. How can I find out the problem code without going to a dealership and be charged$100.00?
Remember at the dealership you will get a comprehensive diagnosis and a reasonable repair recommendation, AZ are not technicians and will give you the code period/or recommend a part that may not fix the problem.

i have a grand prix, and my SES light came on the first week i had it as well, i took it to the dealership i bought if from used several times and they couldnt tell me what was wrong. my girlfriends uncle is a mechanic and he hooked up his computer to it and in seconds knew what was wrong with it. the problem was the fuel injectors, so he cleaned them for free (a $200 repair at the dealer). my suggestion is to look for someone liek that or go to autozone and see if they can help you. i'm not a big fan of dealerships after that incident. g/l

You might want to check out:

http://www.scantool.net/products/elmscan_5.htm

This is an OBDII decoder which displays your codes and sensor data on a laptop or PC. It reads all systems so will work with any OBDII vehicle. I have an earlier unit which only reads GM and it has come in handy on several occasions, saving me way more than its cost.
If the $140 is too steep, get together with some friends or family and share the cost, if you like doing it yourself (Saving Money) then you need something like this.
See ya
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