First, the check engine light in my 2000 Honda Passport came on. My mechanic cleaned the egr system and then changed my egr valve, and the car passed VEIP test. However, sometimes the check engine light comes back on again, and disappears when I go back to the shop. Since the car passed VEIP test, the mechicanic said it is ok to drive. Is this true? Second, my ABS light is on. What does this mean?

HI! Sorry you are having some electrical issues. Troubleshooting some possibilities that are quite common. The ABS light, is a safety feature device that prevents wheel lockup. ABS is short for Antilock Braking System. I am curious to know if your Mechanic knew or didn't know that your ABS light is on. Proclaiming that it is safe to drive, or if it had just recently, began to illuminate on your panel.... since it is a safety feature device, is not safe to drive at all until the problem is fixed. Your car passing your VEIP test, means you are emitting clean air emissions. (No leaks, exhaust, & other pollutants/debris into the Air) The people conducting these particular emissions tests are certified to do, only this type of testing at your local Department of Motor Vehicles. Could be a faulty Ground/ Sensor or Relay. Since your ABS is on, it could be a bad wheel sensor. (Have a Reputable Auto Parts Store or Mechanic, run a connector lead through a Digital Multi Meter Device) Your particular ABS Sensor, is located in your Fender Well and to be "tested" there, at the connector plug. You should be around to make sure what reads on the screen is true, It is easy and a free service. So, don't let anyone charge you. The screen on the Digital Multi Meter should be between 1,000-1,6000 OHMS. If it reads something otherwise, Replace your ABS Sensor & your light will go out. .......(hence, check engine light should also go away if fixed properly with ABS Sensor. Good Luck and hope this gives insight to the root of your problem with your Passport Vehicle. :)

If there aren't any codes pending or in the history, it's really hard to say why the engine light would come on. Sometime things have to be more consistant in order to diagnose. You might want to get a second oppinion. Find a shop that will check the engine light for free and go from there. ABS is anti-lock brake system. When that light is on, the abs isn't functioning. You'd have to have it diagnosed to find out why.