FOAMING in the P/S reservoir ?

[pbm]

I drove my b-i-l's 2000 Neon last weekend and heard a lot of moaning/groaning when I was parallel parking in the city. I looked at the P/S reservoir right after shutting down and it was foaming like crazy. It almost looked like it was 'boiling' but it wasn't very hot to the touch. A minute after shutting down the foaming went away and the fluid didn't appear too dirty. What would cause this foaming?
What do you guys recommend to prevent this?

 

[MaximaGuy]

Foaming means air in the closed loop system. Change the PS reservoir cap, check the fittings to pump and rack for leaks.

 

[Kuato]

Yup, low fluid or dirty fluid, or both. After 8 years, some fresh power steering fluid won't hurt.

 

[pbm]

Does the Neon take ATF or PS fluid?

 

[onion]

I don't know how the reservoir is set up on a Neon. But if it's a remote reservoir like a lot of imports, then sucking air at a supply line or fitting is also a possibility.

 

[RF Overlord]

Originally Posted By: MaximaGuy
Foaming means air in the closed loop system.
I had the same issue with my old Taurus...somehow I goofed when flushing the P/S and ended up with a Vesuvius of ATF...made an awful groaning and whining, too. Once I figured out what had gone wrong, no more foaming like a rabid raccoon...

 

[pbm]

RFO: When you say a "Vesuvius of ATF", do you mean that you had air in the system or that using ATF (instead of PS fluid) was the problem?

 

[Kestas]

I've exchanged fluid many ps systems. Taurus/Sable was the only one that gave me a hard time burping air out of the system. The Taurus folk mention using vacuum to burp air out of the system.

 

[mechtech2]

The Ford strategy of vacuum bleeding PS systems is a horrible joke.
A royal PITA that may or may not work.

Anyway, the noise was from the air in the fluid. When it cools note if the level is low. To have aeration suddenly would be odd if nothing was ever touched. But low could do it.
Also, the return may be sucking air.

 

[meep]

a hard-driven chrysler will do this, even with proper fluid. our minivan started this after my x-bil drove the he77 out of it. nothing weird, just drove it hard. replace fluid with oem spec.

M

 

[RF Overlord]

Originally Posted By: pbm
RFO: When you say a "Vesuvius of ATF", do you mean that you had air in the system or that using ATF (instead of PS fluid) was the problem?
Vesuvius meaning a volcano of ATF due to air and having too much fluid in it.

Ford specifies Mercon ATF in their steering systems, not P/S fluid.