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Question

IMRC Problem and Check Engine Light

May 9, 2017 7:53PM PDT

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.

Discussion is locked

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Answer
read code yourself
Jun 13, 2017 8:22PM PDT

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.

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Answer
MAP sensor probably needs replacing
Jun 13, 2017 9:02PM PDT
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Answer
IMRC problem
Jun 18, 2017 11:35AM PDT

IMRCs do have to be replaced from time to time, but is not a 'common' issue. They can also 'stick' in the open position. Snap-On has a machine called a "MotorVac" that cleans the fuel system under pressure.
Included in this service is a thorough cleaning of the intake/plenum and the MAF sensor (which in this case has nothing to do with IMRC). 70% of the time, this will also clean the gum/varnish that causes the IMRC to stick. You've probably not noticed any drivability issues with it stuck? The problem with just ignoring it is, if something vital happens, you won't know it because the CEL is already on. Take it to a shop that has a MotorVac and try that first. It should be done every 40K, so you could look at it as maintenance even if it doesn't fix the problem. That service, alone, will give better performance an fuel economy. (I have nothing to do with Snap-On, just been using their equipment for over 40yrs)