check engine fault light on

Hi, First, loose gas tank cap can do that. If that's not it, extract trouble code. Pep Boy does that for you free. I use OBD II scan software with my laptop. Using this software, I replaced O2 sensor, knock sensor on my son's 2000 Impreza RS. Tony

Go to Auto Zone and ask them to read the check engine fault code. If you go when they're not really busy, it happens pretty quickly. If they're busy you'll have to wait.

Once you have the code and description, post again here for possible issues.

As another poster said though, tighten your gas cap -- the evaporative pressure sensor in the fuel tank will trip a check engine light (cel) if the cap is not sealed.

Best Regards,

-- Todd H.

On Fri, 9 Nov 2007 21:53:56 -0500, Tony Hwang wrote (in article ):

Even if the gas cap is the problem, tightening it probably will not turn the light off immediately. You'll have to drive for some miles before the thing resets.

If it has been more than two driving cycles with the light on it won't ever clear on its own.

I had that problem, it was a Catalyst problem.

I had that problem, it was a Catalyst problem.