Logged boost vs mechanical boost.

darkness

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Jul 15, 2009
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I recently was able to hook up my mechanical boost gauge. It reads 50% higher boost than what my cts3 gauge reads thru the whole range. Cts3 gauge reads what the tune is commanding. Mechanical gauge was checked for accuracy. I’m at a loss of what could be wrong. MAP sensor? Seems it would follow the tune if it was bad.
 

JoshH

Daggum farm truck
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Is your CTS3 gauge an add on EAS device or is it reading the stock MAP sensor?
 

JoshH

Daggum farm truck
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Feb 14, 2007
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Have you verified the CTS reads the same as a scan tool or other datalogging system like EFILive?
 

darkness

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I don’t have an obd2 splitter to do that, but could check certain areas I know what the cts3 reads. I know for a fact at max boost, the cts3 was reading what the tune was calling for. I was operating on boost map b and my max boost is 37psi. Boost was 24 on the cts3 and baro was at 13. And the mechanical gauge was 35psi.