while parallel parking with vechile in gear (both forward or reverse), with foot on the brake pedal, the vehicle loses power steering. At times, when slowing down on sharp corners the steering is lost also. Any ideas? I have taken it to 4 mechanics who suggested it was the steering pump & steering box - both have been replaced with no changes in performance.

look for a slow leak, it sounds like you may have an air pocket in the power steerign system. You may also want to have the system bled to ensure no air is in the system.

look for a slow leak, it sounds like you may have an air pocket in the power steerign system. You may also want to have the system bled to ensure no air is in the system.


why would this draw down the rpm only when the engine is at the 160-180 degrees (normal operating temp)? When the engine is cold it runs fine...at the slower speed i need to keep one foot on the brake & the other on the gas to keep the revs at 1000 rmp.

why would this draw down the rpm only when the engine is at the 160-180 degrees (normal operating temp)? When the engine is cold it runs fine...at the slower speed i need to keep one foot on the brake & the other on the gas to keep the revs at 1000 rmp.

Well I really couldn't see the power steering pump slowing the engine down, unless there was a blockage in one of the lines and the added pressure from the lines is forming back-pressure on the pump this would slow it down some but most likely the belt would squeal from it slipping around the pump pulley.

there is a chance your Idle Air Control Valve is bad.
You could check it:
-Start engine.
-turn on A/C.
-Turn the steering wheel one direction just enough to activate the pump.
and watch the TACHOMETER, it should remain steady or increase slightly.

Now, I have done this test a few times on my ZJ with a new IAC Valve and my RPM's dropped about 100 rpms, then went up again.

the IAC valve has already been changed twice so we're still at a loss. the jeep has been taken to 3 dealerships already without any help...

Just a guess here, have the hot idle speed increased to the high end of the spec range. It sounds like the problem is mostly at low engine speeds where the pump flow is at its lowest. You are expecting a rapid response and the pump is not keeping up with the demand of the speed you are turning the steering wheel.

To double check this, do the same manouvers, only turn the steering wheel at half the speed you did when the "check steer" condition happened.

Could also be a mechanical problem in the linkage too.

JD

thanks for the suggestions...we'll give it a try

Just a thought but do you have full time 4 wheel drive?