Power Steering Not Working but no visible leaks

[whalenlg]

Finished replacing the torn seal and rack back in the car.
Pretty much back where I started - steers back and forth easily on the stands, but when go out for a drive it is very heavy and spurts power every so often.
I'm suspicious that the flow is still low (see video) even when revving?
Can anyone compare to what the flow looks like in their reservoir when idling?
Only things I can think of now are
replace reservoir
replace the ps pump even though I just rebuilt it and it doesn't leak

[Tom]

Finished replacing the torn seal and rack back in the car.
Pretty much back where I started - steers back and forth easily on the stands, but when go out for a drive it is very heavy and spurts power every so often.
I'm suspicious that the flow is still low (see video) even when revving?
Can anyone compare to what the flow looks like in their reservoir when idling?
Only things I can think of now are
replace reservoir
replace the ps pump even though I just rebuilt it and it doesn't leak

My pump is sitting on my bench if you want to try it...

[whalenlg]

Thanks for the loaner - but no change in behavior.
I also blew compressed air into the return line, through the rack and pressure line and there are no obvious blockages.
At this point, I think it's time to get a rebuilt rack + pressure line + return line to eliminate the rest of the potential issues.
Any recommendations for the pressure and return lines that connect to the rack?
Cohline vs OEM?
(I've seen Hamburg and Uro, but I think I'll keep my distance).

[rheidtman]

I rebuild the 944 racks and have a number of cores on hand...
Rate is $375 plus a core charge, or return of your old unit. PM if you would like more info.

Rick
Oak Creek, WI

[Tom]

I rebuild the 944 racks and have a number of cores on hand...
Rate is $375 plus a core charge, or return of your old unit. PM if you would like more info.

Rick
Oak Creek, WI

Does this sound like a bad rack to you?

[Damo]

@whalenlg have you replaced the reservoir? It's a consumable item as it has a filter in the bottom. Easy to find as it's common across many Euro cars.

[whalenlg]

@whalenlg have you replaced the reservoir? It's a consumable item as it has a filter in the bottom. Easy to find as it's common across many Euro cars.

Yes - I swapped in a new reservoir when I tried Toms known good pump.

[rheidtman]

I rebuild the 944 racks and have a number of cores on hand...
Rate is $375 plus a core charge, or return of your old unit. PM if you would like more info.

Rick
Oak Creek, WI

Does this sound like a bad rack to you?

This is surely a brain teaser! My initial thoughts are it's not the rack, but rather an issue with failure to maintain pressure within the system. That said, it's also possible there is something amiss within the rack - spool valve? I also hate to throw parts at problems...

[rheidtman]

I rebuild the 944 racks and have a number of cores on hand...
Rate is $375 plus a core charge, or return of your old unit. PM if you would like more info.

Rick
Oak Creek, WI

Does this sound like a bad rack to you?

This is surely a brain teaser! My initial thoughts are it's not the rack, but rather an issue with failure to maintain pressure within the system. That said, it's also possible there is something amiss within the rack - spool valve? I also hate to throw parts at problems...

I wonder if one of the metal lines or banjo fittings on the rack are bad/pinched...????
Also, confirm you have the lines properly connected in the right location... more than one person has installed some the lines in the wrong position. Check the two lines that connect to the two open ports in this pic... If you have them backwards, you will surely have all the issues you are experiencing.

[whalenlg]

Thanks for the suggestion - but I had them correct - pressure hose on bottom and return on top of the gear housing. The other 2 metal hoses matched pictures I've see online.
I am pulling all the hoses and will have them checked/rebuilt to rule those out. No visible pinches in the rack metal hoses and air flows fine through them.