Q: EGR valve and vacuum

asked by on February 17, 2016

The Check Engine Light is on. According to Advanced Auto, it shows that the EGR valve and EGR vacuum modulator may need replacement or to be cleaned.

If you got code P0401 for the EGR system malfunction, then the system would need to be tested to see whether or not the vacuum modulator valve is holding vacuum and can control the EGR valve. These tests are needed to see if the valve and modulator are good or not; the EGR tube could be in need of cleaning. If all this is done then a proper diagnosis can be given. I recommend having a mechanic, such as one from YourMechanic, run a diagnostic to see if your EGR vacuum modulator requires replacement, or if another path of repair will be necessary.

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