Is KL01-18-741 the correct part number for all three of the solenoids in that area underneath the rear of the upper intake manifold? As I've never had to take the upper intake manifold off, I'm thinking it might be prudent to replace all three while in there. I'm the original owner of a 2004 and the solenoids are all original.

 

yes, that is the correct Mazda part no.

they charge a small fortune for those, I was thinking you can get them cheaper from an auto parts store, but am not 100% sure on that

 

just posting some helpful info (at the end of this link) to make up for this otherwise confusing, misleading, and all-around unhelpful thread for resolving a P0076 DTC/CEL Code

https://www.rx8club.com/series-i-tro...ooting-271936/

in general, for this code there is either a bad solenoid, a wiring short/ground, broken wire, or dirty/bad wiring connnector in the VDI solenoid control circuit. The PCM is sensing low voltage after the solenoid is engaged. Meaning the electrical circuit is poor, weak, or incomplete.
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