How to identify the culprit behind power steering problems

89gte

Regular
Apr 26, 2011
134
0
0
Tennessee
I searched and sifted through many threads, but I couldn't find the answer to my issue. Power steering is weak at low RPM's, it turns fine once I start moving. How do you know which power steering component is failing? Trial and error? I noticed many threads said that the rack needed to be replaced due to worn out seals and severe leaks. I have made sure my PS fluid is good, but the problem still persists. No leaks. No strange noises. How can I tell whether it's my pump or rack? Thanks in advance.
 

89gte

Regular
Apr 26, 2011
134
0
0
Tennessee
89+. I have spent the last 6 months doing a full rebuild w. MHG, forged pistons/rods, etc. Car will be going again next week. Problem was occurring before rebuild, but I did not have the finances to secure a new rack during the build (I know it was the best time). If I have to pull it back out if it comes to the rack, it'll have to be done. Would the screen replicate these problems? I'm trying to figure out what kind of circumstances could cause this particular issue. Thanks for the response.
 

radiod

Supramania Contributor
Dec 13, 2007
1,342
0
0
37
Abbotsford, BC
Clean the screen and see what happens from there. Could just be slowing down the flow enough at idle that when you bump up the throttle it picks up the slack.
 

89gte

Regular
Apr 26, 2011
134
0
0
Tennessee
I will check the screen. I have had the vacuum line that attaches to the bottom of the accordion hose hooked up, but I will check it out to be sure everything is good. Thanks for the replies.
 

Dirgle

Conjurer of Boost
Mar 30, 2005
1,632
0
36
41
Pauma Valley, CA
GrimJack;1861583 said:
Just checking... it is running auto transmission fluid in there, not power steering fluid, right? Power steering fluid does odd things to our system, it's designed for ATF.

That's the truth. I recently picked up another supra that had power steering fluid in it and the thing sounded like it was ready to grind the bearings. Flushed and filled with ATF and it returned to being smooth and quiet.
 

89gte

Regular
Apr 26, 2011
134
0
0
Tennessee
psplugs.pngI found two plugs under my intake manifold - one coming from power steering, and one on my wiring harness that is not hooked up to anything else. Here is a picture I took, the plugs I mention are circled in red. The plugs will not mate up but the white plug reaches all the way to the gray plug. I do not know all the previous history of my vehicle, but I have reason to believe another 7mgte was swapped in by the previous previous owner. Could the connector from power steering have been from a different year from the engine wiring harness causing it to not mate up properly with my wiring harness pps? I'm not sure of a change in connectors between years. For others who have PPS, do these look like your power steering connectors?
 
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89gte

Regular
Apr 26, 2011
134
0
0
Tennessee
GrimJack;1861583 said:
Just checking... it is running auto transmission fluid in there, not power steering fluid, right? Power steering fluid does odd things to our system, it's designed for ATF.

GrimJack,

Sorry I missed your post from before. I'm not using PS fluid. I'm running ATF Dexron V or VI.