Throttle Position Sensor (TPS) are relatively simple to replace. I recommend that you purchase a chiltons manual for your year and make, it will give you step by step instructions on how to perform this repair. Look in the index and find the explanation about the (TPS) and proceed as they suggest to perform the repair.
While the check engine light may be reading a bad TPS sensor, this doesn't necessarily mean that the sensor is bad. Many times there are other problems which cause it to read bad.
You should have a complete diagnosis done by following a flow chart to fix this problem. I would hate to see you spend the money on the TPS senor only to find out that this does not fix the problem.
If this truly is the problem, you may be able to replace it yourself if you have the proper tools and know it's location.
〉 Answered on Oct 17th, 2007 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines
Your throttle positions sensor is located on the throttle. It is probably screwed in and has an electrical connector. Sometimes they are very easy to get to, but sometimes they are not. If you can see yours, it is really just a matter of unscrewing it, disconnecting it, plugging the new one in and re-attatching the new one. As always, be careful if you are working on a hot engine. If you are unsure of yourself, ask for help.
〉 Answered on Oct 17th, 2007 by Suzanne Grego, Technician at City of Philadelphia Fleet Management