Hello,
at 6.1-6.3rpm my boost starts to drop from 27 to 10psi. Before that everything is fine!
It happened as followed: I tried a 24psi map and everything went well. Then I stepped up and loaded up a 27psi map, and the car didn't boost right at around 6.1-6.3rpm. This happened everytime. I changed back to the previous 24psi map and the same thing started happening. Because of that, I'm pretty sure it's hardware related.
The engine is clearly trying to boost, with wgdc up to 100%, but it's just not happening. Something is hindering it, but only at 6.1k rpm.
DME Code:
30FC Turbocharger, charge-air pressure too low: leak tightness
Possible causes
Boost leak:
Too much backpressure/induction resistance
Other misc
My setup:
(Log is made with oem LPFP, rail pressure is higher with walbro LPFP.
at 6.1-6.3rpm my boost starts to drop from 27 to 10psi. Before that everything is fine!
It happened as followed: I tried a 24psi map and everything went well. Then I stepped up and loaded up a 27psi map, and the car didn't boost right at around 6.1-6.3rpm. This happened everytime. I changed back to the previous 24psi map and the same thing started happening. Because of that, I'm pretty sure it's hardware related.
The engine is clearly trying to boost, with wgdc up to 100%, but it's just not happening. Something is hindering it, but only at 6.1k rpm.
DME Code:
30FC Turbocharger, charge-air pressure too low: leak tightness
Possible causes
Boost leak:
- Leak tested the whole system with around 20psi, no leak
- Tested oem and aftermarket blowoffs
- Manifolds and CHRAs looks tight as well
Too much backpressure/induction resistance
- Inspected cats and inlets with endoscope, everything seems fine
- I could endoscope one compressor, no visible damage
- unlikely that both turbos are blown. AFR and STFT are similar across banks
- Vacuum system is tight (new vacuum hoses, system holds vacuum)
- Both solenoids are new
- Manually tested wastegates. Fully closed at 180-190mbar (BMW specification is 200mbar)
Other misc
- Tried my original LPFP, made no difference
My setup:
- 19t turbos
- 2" inlets
- walbro 525 pump
- big fmic
- original exhaust system: empty pre-cats, 200cpsi main cats
- 2 steps colder + gapped spark plugs
- alu cp
(Log is made with oem LPFP, rail pressure is higher with walbro LPFP.
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