Forum Discussion

lfeather's avatar
lfeather
Explorer
Aug 27, 2015

7-14 psi turbo boost when engine compression brake engaged

With, as always, zero torque and 256 mpg as shown on silverleaf. Anyone have any ideas why this would occur? I wouldn't think that turboboost should activate with engine compression brake engaged? TIA
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Ivylog's avatar
Ivylog
Explorer III
Aug 27, 2015
I checked mine (ISL 400) on the way home today and depending on RPM I had 12 to 15 psi with the 15 at 2000 rpm. Sounds normal to me as there is still exhaust gas going through the turbo when you have the Jake on, but not as much if you have your foot in it.

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