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Tots February 7th, 2015 13:27

Air in power steering steering system
My question is this can air get in the power steering system from the rack?

My 2002 jetta has had air in the power steering system since i replaced the rack and pump about 4 months ago.

Both the rack and pump came from my parts car. I originally figured the used pump was bad so i replaced the pump about a week after the original work but i was still getting air in the system.

I have replaced the pump and the hose clamps on the low pressure side. Is there anywhere else air can get in the system?

yatzee February 7th, 2015 13:45

could be a leaking line or seal

Lug_Nut February 7th, 2015 14:01

The system is pretty much pressurized the whole way, even the return side is under a bit of pressure. Fluid would leak out before air leaked in. There is no pump 'suction' applied on the return so air isn't getting sucked (pushed by higher atmospheric pressure) in. The system is 'self-bleeding' in that within a few lock-to-lock turns any air would be pushed back into the reservoir and to atmosphere.

However, if the reservoir is low the pump could very well be moving a froth of air and fluid into the system and making a continually air affected system.

Is the rack one that was purchased based on price? The "New! VW! OEM!" steering rack, may well be one from VW China. If it's like the one I put in my Jetta, it has a weird sensation, almost a dead spot, when the steering wheel is moved from left to right, not from right to left, not while being held steady, and not while in the act of turning the wheel, just at that instant when a left turn of the steering wheel ends and the wheel is begun to be spun back to the right.
C.R.A.P. strikes again, and lesson learned.

Tots February 7th, 2015 14:05

no fluid is leaking out of the system so the high pressure lines are good. I replaced the hose from the pump to the reservoir. Maybe the return line from the rack?

Tots February 7th, 2015 14:10

the rack is from a parts car so it could be bad. The reservoir is not low I was trying to bleed the system this morning with a new pump and hose. If i cant get the air out i plan on putting the old pump back on until i can get a new rack.

gforce1108 February 8th, 2015 06:26


Originally Posted by Tots (Post 4732471)
the rack is from a parts car so it could be bad. The reservoir is not low I was trying to bleed the system this morning with a new pump and hose. If i cant get the air out i plan on putting the old pump back on until i can get a new rack.

From what I remember, the procedure to bleed the air is to lift the wheels off the ground and turn lock to lock with the car not running. The rack will suck/push the fluid through instead of relying on the pump.

Tots February 8th, 2015 08:05

I wish i had a simple problem that could be fixed with bleeding the system.

Reading this forum has been enormously helpful in fixing my car. It has gotten me through rebuilding the engine after catastrophic timing belt failure and converting it to a manual. I have read many threads on power steering problems involving air in the system. All of those problems were solved by replacing the pump or the low pressure hose. Or more commonly adding fluid to the system. I have done all of these things, I have even bought a second power steering pump just in case.

There are still three components that could be the source; the return line, the rack or the high pressure line. I don't want to replace all of them.

I have been using my mityvac to remove the air and assist in bleeding the system. It is attached to the return line where it connects to the reservoir. The hose that connects to the pump has been plugged. In doing this i hoped that applying vacuum to the system would allow me to hear where the air is entering the system. Air is indeed entering the system, but i could not quite pinpoint it. So i applied pressure to the system too see bubbles or a fluid leak. Nothing i could pressurize the system as much as mityvac would let me.

So the system would not hold vacuum at all but it would hold pressure.

Any thoughts?

Tots February 8th, 2015 10:18

There is a check valve in the bango bolt that connects the high pressure hose to the steering rack so that explains why i can pressurize the system. Because i am only pressurizing the return line and the rack.

Therefore the problem is in the high pressure line. or the connection.

I did not know about the check valve

Tots February 8th, 2015 15:59

Turns out it was the washers on the banjo bolt. They were new when i swapped the transmission but i did not replace them when i swapped out the steering rack. I did not suspected them because they were not leaking and since they are on the hi pressure line i did not think that air could enter without leaking fluid. I was wrong.

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