Loss of half power after dp install

Jcool493

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Hey everyone, amateur car enthusiasts here sorry for my stupidity. So recently ive installed a downpipe and frontpipe on my civic(2018 ex-t) and for a month it ran fine than recently it felt like half the hp was gone and it felt like a naturally aspirated, it started to throw p0139 and a p2187, I assume it was a boost leak heard it could be fuel injectors, dealership won't work on it because of the aftermarket parts so any help would be greatly appreciated.
Thanks,

2018 civic ex-t 30000 miles
Ktuner stage 2
Prl race maf Cai installed year ago
Prl street downpipe/fp

Edit: don't know if it matters but ktuner is reading a max boost of 3.90 psi
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P0139 is normal for a downpipe, its just the O2 sensor not seeing the proper amount of exhaust gas vs. the stock downpipe.

P2187 is more concerning. Are you running the proper tune with a Race MAF calibration?
 
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Jcool493

Jcool493

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Yes the ktuner stage 2 with the prl race maf selected, ive had the Cai for a year no problems up until now,
 

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Yes the ktuner stage 2 with the prl race maf selected, ive had the Cai for a year no problems up until now,
Just wanted to rule that out as it's an easy mistake people make. Definitely seems like a boost leak to me. First thing I would check is no couplers have come detached. Check everything from the throttle body backwards through the charge pipes and intercooler to the turbo outlet. If that all looks good I'd look at the downpipe as it's more work. Did you re-use or replace the gasket from the turbine housing to the downpipe? Likewise for DP to FP?
 
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Jcool493

Jcool493

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I re used the gaskets, at work now but I'll check all the piping when I get home
 


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Jcool493

Jcool493

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UPDATE
So umm I did some research online and all forums say it could be the Bypass valve. So I disconnected the wastegate wires so I didn't bump them, and re seated the vacuum hose on the bpv and wires, flashed it to a tsp tune and it seems to work? IAT good, afr good, no codes, boosting properly, so I guess loose vacuum line on the bpv(not sure), maybe it was stuck and messing around opened it. probably gonna have to look into getting a boomba bpv unless you guys think it could be something else. Anyway thats all for now, I'll keep an eye on it and thank you guys for replying
 

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Jcool493

Jcool493

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Are they bad? Hey I never said I was smart, and I'm not young enough to understand a sentence of emojis, please explain
 

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Are they bad? Hey I never said I was smart, and I'm not young enough to understand a sentence of emojis, please explain
VTA BPV are not good for the L15. If you want an aftermarket BPV, get a recirculating one like the HKS, other than that, just stay with the OEM.
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