Hyundai Repair: engine light, fuel management system, transmission control module tcm

Question
2002 Hyundi Elantra 4 cylinder engine ligt stays on  

Answer
An illuminated check engine lamp indicates that the engine control module (ECM) is alerting you that it's detected a problem with your vehicle's fuel management system or that the transmission control module (TCM) has made a request for the ECM to illuminate the lamp.  As long as the vehicle drives normally and the lamp doesn't flash, you're typically okay to continue driving the vehicle but should have it checked in a reasonable amount of time.

Unfortunately, without the diagnostic trouble code(s), I cannot tell you the nature of the problem.  The list of diagnostic trouble codes that could cause your check engine lamp to come on is about 30 pages long.  

Depending on the problem, the original sale date of the vehicle, and the vehicle mileage (basic warranty 5 years/60,000 miles), the issue may be covered by your factory warranty.

If you'd like to investigate further on your own, AutoZone and AAMCO have advertised they'll read diagnostic trouble codes for free.  Since we don't know whether this is a transmission or engine issue, you should probably have them read both the ECM and TCM trouble codes.