2004.5-2007 ISB boost solenoid question

[PTECH]

Can anyone tell me what frequency the PWM signal is sent at to the boost solenoid?

 

[CKelley1]

I was troubleshooting a problem and had a oscilloscope hooked to the solenoid. here is what I seen. until the ecm calls for more than 20 psi boost there is no signal at all. above 22 psi a 5 volt pwm signal starts to appear, I did not look at the scope to see if the frequency changed but at full boost the pulses were about 50% wide. we found we could take a 147 ohm two watt resistor to fool the ecm and convert the solenoid to a adjustable boost elbow. unless you have a fair shop a easier way is to use the 147 ohm resistor and add spring tension to the diaphragm to increase opening to 33 psi. cut the leads off of the solenoid and attach the resistor to the leads and plug it in the truck harness. if you need more info on how the solenoid works pm me with your email address and can send info and pix