ok so i'm getting the EGR valve code (p0401) on a 00 prelude. that's not really a big problem. i cheked the valve it's in good condition (vacume test) and i cleaned it up real good and still getting the code. that only means the sensor itself or the selenoid is defective. what voltages should i look for for proper working sensor and selenoid? i know the sensor comes as a full unit with the valve but is there a way to just replace the sensor if that's all that is wrong?

thanks

 

Probably the ports are stopped up. Need cleaning, but this can be a major task on preludes if the ports are cast over instead of freeze plugged into the IM which most of the later ludes were.

 

ya if you can tell us or get a pic of the port caps we can give you the process needed