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Fast Freddy Mar 7, 2025 03:57 PM

P1487 help
 
Gotta check engine light p1487 2002 1.8. Some peeps say boost sensor, some say egr valve and other say solenoids. Any suggestions here or testing tricks? Thanks.

ConeCrasher Mar 7, 2025 08:48 PM

If I remember correctly the boost solenoid code is caused by a port in the intake manifold being blocked with carbon.
involves removing upper intake and cleaning the egr port all the way down to a hole behind the throttle body.

themonkeyman Mar 8, 2025 03:10 PM


Originally Posted by Fast Freddy (Post 1662427)
Gotta check engine light p1487 2002 1.8. Some peeps say boost sensor, some say egr valve and other say solenoids. Any suggestions here or testing tricks? Thanks.


The “boost sensor” or “Egr valve” descriptions are generic codes from other manufacturers, for Mazdas of that era p1487 is for the tumble valve/VICS flap solenoid. Check that it’s working (should be able to hear it click when jumping it with +12v and ground—polarity doesn’t matter) if you get a nice click with voltage applied, make sure the vacuum lines are in good shape. If all the above checks out, might be clogged with carbon internally like mentioned above.

However, I don’t think the ECU can really “see” a conditional change when the flaps are activated, I think the ECU just runs continuity/resistance checks through the solenoid. So it’s likely a dead solenoid.

Where in CA are you? I’m in LA (Silver Lake) if you want a hand diagnosing it :wavey:

Grubsoon0 Mar 10, 2025 07:21 PM


Originally Posted by Fast Freddy (Post 1662427)
Gotta check engine light p1487 2002 1.8. Some peeps say boost sensor, some say egr valve and other say solenoids. Any suggestions here or testing tricks? Thanks.

P1487 usually points to an issue with the EGR system or related components. It could be a stuck EGR valve, a faulty boost sensor, or an issue with the solenoids. First, check for any vacuum leaks, inspect the EGR valve for carbon buildup, and test the boost sensor and solenoids for proper operation.


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