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BPC Posted by Ari [Email] ![]() ![]() In Reply to: Re: APC solenoid, Kevin, Mon, 8 Jun 2009 14:33:27 Members do not see ads below this line. - Help Keep This Site Online - Signup |
No, not a resistor change.
The early APC was an analog system, and boost levels could be changed with resistor changes.
The later cars, like yours, have the boost control built into the Trionic controller, and the boost levels are built into the software. Changable? Yes. Easily? No.
In terms of failed boost, the BPC (three wire) valve consists of two coils, with one lead from each coil common. The controller sends pulses to the coils; if the pulses to each coil are the same width, the magnetic field from the coils is balanced, and the valve stays right where it is. The controller sends wider pulses (turned on longer) to one coil and shortens the pulses to the other coil; this unbalances the magnetic field and the valve moves to the new position.
If a coil is shorted, it will destroy the transistor in the controller that sends the pulses. The transistor in the controller can also die.
But as noted, for the newer cars, messing about with the boost is harder.
But the question remains-
Is something wrong with your car? Or is it working fine, and you want to boost the boost?
posted by 192.249.47...
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