Hey all,
My current autocross ride/DD is a 2011 camry 
In the middle of quick transitions e.g. tight slaloms, the power steering seems to seize in place for a split second.
Is this just the pump not being able to keep up/cavitation, and is it actually doing the power steering system harm or accelerating wear?
Thanks!
I am not sure if the 2011 camry ps system works some unique way but it sounds very much like the pump isn't able to keep up the pressure.
It could also be something to do with the steering rack valve lag causing it to continue holding pressure to the right for a split second before the valving changes to the left. If you were going right and transitioning to turning the steering wheel left.
I had a problem with my 4runner and it was bad belt. Make sure it is a good belt. Mine looked fine. It wasn't.
^this.
Belt is a quick and easy diagnostic. A glazed belt might not have enough bite to spool up the pump under heavy load.
Ah, good point re: the belt, I'll check it out, thanks guys!
Yep, belt first but likely just a pump that can't keep up. No long term damage, just engineers that didn't test enough and put enough priority on making it an autox weapon.
I had the same issues with the Koreans. The Elantra I added a cooler loop to the return line. Fixed it. The Forte I switched over to the Amsoil PS fluid (Supposedly highest boiling point). Both of mine would boil the fluid when used like that. To the point where it would boil over the catch can and make a mess. Fluid would be stupid hot. Didn't help the entire system barely held a quart.
The only vehicle I've had this problem with was a Ford. It was a belt issue.
Ex power steering engineer here.
This is called pump catch. If the handwheel speed is too fast or the load demanded is too high, the system can't keep up. The system is giving all the output it can at a given moment, but the need is more, so it momentarily feels like no assist.
Hydraulic systems do this when the pump can't move enough fluid to assist the rack. Electric systems run out of juice available to the motor.
This problem could also be due to a slipping belt, but in auto cross type situations, I lean to pump catch.
^And if everything is in good condition, this can be caused by the pump's output orifice being too small for the steering speed you're demanding. Been reading up a lot on this recently since I've been thinking of shimming my flow control valve to get more hydraulic assist.
If the belt is fine, also check the fluid itself and flush in fresh fluid if the old is really dark or thick. Fresh fluid will give your pump the best chance of keeping up with what you're asking it to do.
If it's overheating the pump, you could add a cooler. I had to do this. The 22re ps pump does not like autox slaloms
Trackmouse wrote: If it's overheating the pump, you could add a cooler. I had to do this. The 22re ps pump does not like autox slaloms
Most PS systems don't. That's the one thing that autocross is really hard on. It would also help to switch to synthetic ATF (if your PS system uses ATF).
I had a similar issue with a Subaru system. I swapped to red line p/s fluid and it was much improved but still an issue. One of the road race guys I knew also running a subie mention the system pulling air in under heavy use at the hose connections. I said whaaat? Anyway I swapped all the factory hose clamps to worm gear clamps and never had the issue again.
Was a long shot that happened to work for me.
I've had this happen in the Miata so it isn't just appliance racing, it's just a byproduct of asking the system to do more than it was designed for.
Manual racks FTW?
Trackmouse wrote: Manual racks FTW?
I like the quicker ratio of a power rack for autox. I think with a combination of the fixes mentioned, this can be vastly improved or eliminated.
Had that issue with a Ranger, the pump had a plastic impeller that tossed a fin. Gave it a drink of Lucas and it healed.
Trackmouse wrote: Manual racks FTW?
Electric columns FTW.
Manual racks are usually too heavy or too slow. Converting to an electric column allows one to use a decently fast manual steering rack or box without the leak prone power steering and added weight.
In reply to Stefan: Very correct. I just miss my Datsun manual rack. So much input.
On a Neon Track car I had all kinds of problems keeping fluid in it (foaming/cavitation). Tried coolers and different flavors of juice, no joy.
Then I switched to a Cloud car pump and reservoir which had the reservoir 6" higher and 6" forward of the pump, no more problems.
Well, traded in the camry for a NC club 
Gota say, for what the camry is and its tires, not a bad handling car at all:
Trackmouse wrote: Manual racks FTW?
If your steering effort is high enough to make the power steering urp itself, a manual rack will be a detriment.
My late VW would rallycross okay, but when autocrossing it would lose the power steering as soon as the first corner and it wouldn't come back until I let the engine idle a bit. And a 3000lb very nose heavy AWD car needs power steering.
I always figured that it was because the fluid reservoir was a 2-3' long horizontal run forward to the pump, going to a banjo fitting. Suction side cavitation. Maybe, maybe not. Replacing the ATF with "Goo 2000" seemed to help a little, or maybe I was mentally justifying the expense of $20/liter fluid.
In reply to paul:
Well thas a rather extreme solution 
Had the same thing happen in my Camaro, it was boiling the fluid out of the reservoir and ultimately killed my pump. I did the nuclear solution and added a cooler to the return line as well as replaced the pump with a rather spend your Turn1 revalved unit. Solved it for good.
I was looking for this thread because the Vic does the same thing. Acute turns and slaloms will ruin the steering.
The fluid is 2 years old now, and there's plenty of evidence that the system USED to leak, but the level hasn't dropped since I bought it. Maybe a flush and fill will help.
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