power steering/brake assist issues?

[deezl duly]

hey folks been gone for a while. duallys runnin great , but i recently picked up an issue that seems to be connected to the power assist to the brakes. at idle i have a mean vibration thru the steering wheel and brake pedal. its between 700 and 1000 rpm once i take off its fine. i removed the serpintine belt and its smooth as silk. could it be the power steering pump or maybe the brake assist? dont want to start randomly replacing stuff. any of you ever have this type of problem? thanks in advance for any and all help.

 

[bison]

did you check the motor mounts?

 

[deezl duly]

yea mounts are good new vibration dampener/ pulley,water pump alt, flexplate, checked converter bolts, all good. if i remove the belt and restart it, its smooth thru the whole power band. im baffled. 11000 mi. on new engine.

 

[JMJNet]

Did you check the pulley? Bearing may be gone.

The harmonic balancer and crank pulley are very important.
Can be checked visually although you may need to take it out for inspection.

The power steering high pressure hoses are also prone to leak with age.

 

[deezl duly]

yes i checked all those things. they were all replaced when i put in the new motor. i removed the belt again and spun , and tugged, and pushed on all of them. they all spin good with no excessive play.there used to be a small whirring sound the first time i would hit the brakes backing out of the driveway, that i no longer hear. my guess is that the little pump between the firewall and the master cylinder has given up.im gonna price them today and start there. it still runs and drives fine just very irritating at stop lights. thanks for the replies, ill let u know how it goes.