Hey I just bought a 02 Lacer Es a week ago....my engin light is now on......I hooked up the thing and it said cylinder 3.....not sure what to do ....this is my 1st car and im not good with cars atm

 

It might be a misfire if it says cylinder #3. Bring it to a shop to get it checked out. Have a professional before you regret doing anything drastic

 

^+1
If you don't know alot about cars then it's time for a shop to look at it.
Or you could take it to AutoZone and have it scanned and they may be able to help as well.

But I'd take it to the shop.
~Micah

 

Also I'll add it could be as simple as a bad or mis gapped spark plug.
Or it could be big, but most likely not big.

 

autozone and shops like that usually only scan it and tell you what the code is, i would follow Micah's advice and head to a reputable shop

 

If it's only been a week. I'd take it to the dealer you got it from and have them fix it or money back. 30 day warranty if I'm not mistaken. But knowing them...they prolly just cleared the code and hoped it didnt come on during test drive. But you can take it too a reputable shop and get an estimate and have the dealer/seller pay for it. Not unless you bought it "as is". I'd never do that not unless I had big plans from the start.