Running well, but boost keeps climbing

Turbooooh

Greenie N00B Member
ENGINE/DRIVABILITY
**
Feels great, AFR looks good, but boost (18 PSI+) seems to be climbing higher than I feel comfortable with. Up to 23 PSI!
Logs uploaded. Please advise.
*Also, the horn doesn't work and brake lights don't work..? Ugh...
**Update: found fuse #38 (horn and brake lights) blown in the passenger side fuse panel due to a cracked bulb socket in the driver's side tail lamp.
**
Year/Make/Model:
2007 Mazdaspeed 3
Mileage: 207,000 miles
Location/Alitutude: Missouri Ozarks
Concern: Requesting log reading to identify concerns
DTC's: PCM: P0571(cruise control/brake switch A circuit malfunction - found blown fuse), P0421 (Warm up catalyst below threshhold (bank 1) - ebay downpipe?), IC: U2064 (no description), P0403 (egr deleted),
Modifications: Mazdaspeed Intake, 2"ish Turbo Inlet pipe, stock-size replacement turbo, Ebay Downpipe (12 years old and still in great shape!), Autotech HPFP, Aftermarket top-mount IC (unsure of brand), aftermarket BPV, Grimmspeed EBCS
ECU/Tuning Software: Cobb Accessport V3, currently on Stage 0 - 91 - v400 for testing
Tuner: n/a
Is the concern intermittent? No
Can you duplicate the concern? Yes
Recent Repairs: Replaced rod bearings and rings on 4 pistons, deleted balance shaft anchor(!) and installed plug, reinstalled recently replaced timing parts (chain, VVT, tensioner, etc), new Autolite iridium spark plugs gapped to .028
Attempted these corrections: n/a
Correction: P0571 - brake light/horn/cruise control fuse blown; #38 in the passenger side fuse panel
 

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P0571 code update: As mentioned in the initial post, I found fuse #38 (horn/brake light/cruise control) blown in the passenger side fuse panel. I'll get some new 10A fuses and confirm the fix.
PS_FusePanel_38_hornbrakelight.jpg PS_FusePanel_hornbrakelight.jpg
 
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Adding another log.
It feels SOOO good after driving a Ford Fusion for the last several months, but this is wigging me out.
It spiked at 23 PSI this morning and I'm not even putting my foot down, then immediately let off when I see it jumping up.
Is my Wastegate not working?
Line 80: up to 19 PSI
Line 954: 22.59 PSI
Line 1500: 18.2 PSI
Line 1789: 22 PSI
Please advise.
18.1.png 19psi.1.png22psi.1.png 22.5psi.1.png
 

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Solved!
But not yet resolved. I now need to buy a wastegate actuator with the proper length arm or an adjustable arm. See the attached pictures. 5 1/16” stock turbo with the wastegate flapper closed versus the stock size replacement turbo at 5 1/2”. Ignore the parallax error on the pictures. I verified the measurement multiple times.6B1E3C61-A8E3-4350-AB3D-FC3613EEDCA5.jpeg1EB07F9A-FFEC-449E-B1DF-7A5E717CC883.jpeg
 
Resolved! Lengthened the waste-gate arm 1/2” by threading the arm and using a coupling nut. It’s now holding a steady 15psi with my foot on the floor.
Apparently the “k04” replacement turbo has some extra meat on the frame or housing and with the stock length actuator, it was not opening the waste enough or maybe at all causing the boost to hit 23psi+.
FE036904-BED6-46B6-954E-8758B0560EAF.jpeg
 
Thank you for the update on correcting your issues. Watch that circlip that holds arm to wastegate arm. Mine had a slight misalignment and the circlip decided to flee. Had to source a tight fitting one to fix, installing clip in engine bay is no fun.
 
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