What power steering?

[camfoot]

My 97 4wd Tahoe has stiff and unpredictable steering. It seems to wander around a lot. The power steering pump has been replaced with a new one as well as the hoses. The steering dampener as well as all ball joints, tie rod ends, idler arm and sway bar bushings are new. So I know the entire front end is new and tight. It also has a new alignment. The rag joint on the column is in great shape too. Even with all this, the pump still whines and fluid comes out the top on occasion. What is the electrical connection on the pump and what does it do? Does this effect the pressure? The steering gear has been tightened up slightly but the gear is the only thing I have not replaced. It does have a body lift and 33"x 12.5" tires. Everything else is new. Anybody else?

 

[lesterl]

The electrical is for a dump valve that reduces pressure for highway crusing, there is a sensor under the dash on the steering column that can cause erratic steering... might check/ replace it.....

 

[camfoot]

Thanks for the info lesterl. I'll check out the switch.

 

[camfoot]

By the way, where is this switch located on the column and what does it look like? Maybe some pics?

 

[lesterl]

It is a round disc, just on the column search for it, there have been folks that have posted pix of it....

 

[Slammed]

Did you do the Pittman arm?

 

[Zipper369]

I had a similar issue with that sensor. It's called the EVO (Electronic Variable Orfice) sensor. It controls how much power steering assist you get. I disconnected mine to see if that was the issue and now I get 100% full power assist at all times (even when I'm going 65 down the highway). I haven't bothered to replace it yet, but it's definitely strange to get used to driving without it.