If the check engine is steady on, it indicates a minor fault such as a loose gas cap or failing oxygen sensor. If it's flashing which could mean a severe fault occurs, you should stop driving it. Use a OBD2 adapter or scanner to read the codes and google for reasons and solutions.
Hi,
I've got a Ford Focus, 2005. The check engine light went on today. Brought it to an AutoZone and they asked me to plug in a PCM. The results:
"The bank 1 manifold flow valve position sensor signal indicated the intake manifold runner control remained in the ?open? position."
Can someone explain what this means and how I can fix it. Is this a critical problem or an easy fix that I can do? Can I still drive my car to work? Thanks.

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