I replaced the power steering pump (and found out later in this forum I should have replaced the pulley with a Z06 pulley due to it having the holes in it to remove the bolts on the pump). However I did it the old fashioned way and had to remove the brake unit assembly (with all 8 lines) and after replacing the p/s pump and new pulley (C5) I am now in the situation where the steering is VERY hard to turn (as in almost no power steering) as it seems the pump is not functioning. I have done the preliminary turning of the steering with the wheels off the ground 30 or 40 times. I have driven the car over 10 miles through parking lots and such and still VERY hard to steer. What else can I do??? Amy help would be appreciated.

 

The service manual specifies you have to "bleed" the system using a vacuum pump.

Here's the process ....

1) Fill reservoir to FULL COLD mark
2) Attach vacuum pump to reservoir
3) Apply a vacuum of 20 in Hg
4) Wait 5 minutes (pressure change of about 2 in Hg)
5) Remove vacuum pump and replace cap on reservoir
6) Start engine and idle for 30 seconds
7) Turn off engine
8) Verify fluid level (top off as needed to FULL COLD)
9) Repeat 2 through 8 until fluid level stabilizes - put cap on reservoir
IMPORTANT - DO NOT TURN STEERING LOCK TO LOCK
10) Start engine and allow to idle
11) Turn steering wheel 1/2 to 1 turn in each direction. Do this 5 times
12) Turn off engine
13) Verify fluid level (top off as needed)
14) Install vacuum pump and apply 20 in Hg vacuum for 5 minutes.
15) Verify fluid level (top off as needed)
16) Repeat 10 through 15 until fluid level stabilizes
17) cap the reservoir.

See if that works for you.

 

Thanks for the input. What am I going to use to get the 20 in hg? I have a vacuum pump I use for my ac work - will that work? I would have to rig up some sort of valve to keep the pressure in once I get the vacuum. My hand vacuum (Mighty-Mite) seems to have a problem holding a vacuum (it is quite a few years old) so that's out of the question.

 

I would think an A/C pump should work fine ... it should be able to easily pull a 20 in Hg vacumn .... as they are made to pull about 30 in Hg in an A/C system.

You need some kind of "stopper" that you can put in the top of the reservoir (cap area) with the vacuum hose routed through the stopper. maybe some kind of clamp could be used on the hose to "seal" that vacuum once the pump has achieved the right level.

I'd be cautious of trying to get a "pure" vacuum like you try to get with the A/C system .... I don't know if the reservoir is strong enough for that.

Good luck with it ..... I suspect once you get the majority of the air out, the rest will naturally be purged as you drive the car .... just watch your fluid level for the first day or two after the system is working.

 

Thanks - appreciate the info and I'm on my way to see what I can get done. Sure do want to drive this car once again.

 

I did not replace my PS pump, but the Dealership did replace the Rack & Pinion Assy last month (again). Now the car is VERY hard to steer at slow speeds. Been driving it about a month with no improvement. The last time they replaced the steering rack, I did not have this problem. I took the car back to the Dealership and they said there is nothing they can do to improve the problem except order a 4th Steering Rack and install it. They said that I am getting some power assist, so as far as they are concerned they are done?

Wonder if what you suggest would help with my issue as well?

PS - if so, where would be the best place to buy a vacuum pump for this? I guess I would have to buy a spare PS Reservoir Cap and modify it?

 

Well I rigged up a vacuum system and after making sure it wasn't leaking (had to use some sealant to seal it up good) I connected it to my vacuum pump and it held it at 20 in hg for over five minutes. I followed the instructions you gave me and after awhile (about four tries) the fluid level finally started to go down in the resevour and the steering does get better. I quit for the day (prior engagements) and will jack the front end off the floor tomorrow and will hopefully suck all the air out then. I did see that just before I quit when I turned the wheels I could see bublbes (quite a bit too) coming into the resevour. So I will let you know what happens tomorrow. Thanks again for the assistance.

 

Glad to hear things are improving .... keep us posted .....

 

Damn stealerships ..... that is ridiculous that they are saying that they need to put in a 4th steering rack ...... given that most Corvettes NEVER need a 2nd rack .... ya think 3 racks might indicate the dealer is CLUELESS ???????

Here's what I'd do .....

First, check the car to see if any DTC have set by using the DIC procedure. The EBCM, for example, controls the Magnasteer (variable steering effort) function in the car, and a failure of your Steering Wheel Position Sensor will set a DTC in the EBCM, and cause your steering to feel different.

Second, yes, try bleeding the system. Most auto supply places sell inexpensive hand vacuum pumps (one is called Mity Vac ... it is just a "pistol" pump (squeeze your hand closed and you are "pumping" the system) that has a vacuum gauge on it. Kinda looks a little like a pistol with a gauge on top of the barrel and a hose (plastic tube) coming out of where the bullet would normally exit. Then you need a stopper large enough to fit into the top of the reservoir. Some vacuum pumps come with some stoppers ... if not ..... Home Depot/Loews ... plumbing supply shops should carry these ..... just measure the diameter of the opening on the reservoir and get a stopper of a size that will close that opening (if the opening is 3.4271 inches across then a stopper with a base of 2 inches and a top of 4 inches will work perfectly.). Drill a hole through the stopper the diameter of the tube from the vacuum pump and feed the tube through the stopper. Use a sealant if there are leaks around the tube/stopper interface.

Nothing has to be "perfect". So long as you are generating good "suction" on the power steering fluid and can keep that suction up for roughly 5 minutes (maybe you have to pump the handle every 10 seconds on the pump) then it will work.

If you decide, after trying for 19 hours and 47 minutes, that there is no air in the system ( ) then the THIRD step is to have the power steering pump tested. Almost any dealer (Chevy, Pontiac, Ford) and independant shop should be able to do this. The two things they test for are pressure (PSI) and flow rate (GPM). If you find an independant shop that will test the car, post and someone can give you the appropriate measurements to look for.


If the car passes all three tests (no DTC, bleeding, PS pump) then the problem is mechanical in either the rack and pinion system or in the suspension. If you've gotten that far, post again, we can help you figure out the mechanical source of the problem.

 

Thanks for the response. Not getting any codes, so I will try the vacuum pump procedure next.

 

I bled just about everything I could out of the power steering system today, so i went to my parts dealer and chatted with the "ole pro". He told me that i more than likely got a bad pump. To check it he told me to get to the high pressure power steering hose and with the engine running "squeeze" the hose with a pair of long nose vise grips, and if the pump squeals and the hose sort of "torques up" then the pump is ok. If the pump does nothing then the pump is not functioning and it is bad. So I did the procedure and "nothing" happened. So I have a defective pump - now I get to do this all over again. This time i will replace the pulley with a Z06 pulley with the spaces in it so i can get to the bolts that hold the pump to the engine without having to remove the ABS syatem. But - just in case someone can give me other information then I will do the pump replacement - but this time from another supplier. Thanks for your interest and time. i do appreciate it.

 

All hail BlackZ06!!!

Purchased a Rubber Stopper at Home Depot tonight, drilled a hole in it and pushed a hose down through the middle of the plug and connected the other end to an old hand vacuum pump that I had never used. Pumped it up to 20 psig and I could hear and feel the air coming up ever so often. Car steers like a dream now. Many thanks for this post!

A couple other associated things to mention...

The car also was riding really rough in the front end going down the street - like the tires were out of balance (but I knew that was not the case). It did that ever since I left the Dealership after they switched out the Steering Rack. Could air in the steering lines have been causing that effect? Because it went away immediately after I purged the air from the system? Now the car steers easier AND the steering wheel is no longer fighting me somewhat going down the road.

One other thing I noticed was that it was harder to steer to the left than the right - now it is about the same.

 

Well I got another steering pump (from another supplier) and took out the old pump - again. What I did was I went and looked a a C6 power steering pulley at the local stealership in a C6 on the lot and it is in fact "slotted". So I ordered one (will be here today for $25). I just used a crowbar and broke the pulley I had just replaced and removed the pump - along with the bracket holding the pump (three more bolts is all. It looks as though with the pulley installed on the pump there is not much room to install the whole assembly as a unit - but I will do what it takes to install it without having to remove the ABS unit. I am also replacing the high pressure hose this time. I need to get this car on the road - soon.

 

The power steering system works GREAT. I replaced the pulley (C6) and the hose and the new pump and it works just wonderfull. NOW - I have what I believe is a hollowing water pump issue - it never ends does it! SOOOOO I will be looking for info on replacing the water pump. New thread to follow. I want to say Thank You to those of you who gave me information and advice on the power steering issue I had.