Knowledge Base - Info:- What Type of BOV for a Rev1 / 2 Turbo?

The Revision 1/2 3S-GTE engines uses an airflow meter. The BOV fitted as standard is a recirculation design instead of the popular vent to atmosphere design.

A side effect of changing to vent to atmosphere, is the potential for engine hesitation when changing gear under boost. This is believed to be caused by the ECU anticipating a larger airflow than it actually receives. This means that the ECU has fuelled for air that has, in reality, been released to atmosphere. The lambda (02) sensor will measure the excess fuel, and lean off the mixture, which can cause detonation.

Vent to atmosphere is popular because of its loud noise, but owners who have returned to a recirculation BOV have reported an improvement in engine pick up.

It really all boils down to Noise Vs Design!

Pete Jones.

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Created : 2011-10-05 16:34:33, Last Modified : 2011-10-05 16:34:33

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