I would remove the valve and make sure you have vacuum and exhaust present at the valve.
You need to verify the solenoid is working correctly and if it is getting the correct signal from the pcm.
The modulator need to be checked as well but I would look at this last to make sure the rest of the system is working correctly.
Please consider a to help us answer more questions.
Monday, May 28th, 2012 AT 6:53 PM