EVO variable assist...
There's basically three parts to the system; the solenoid on the pump, the box under the dash, and the steering wheel sensor.
If you have replaced everything (pump, rack, fluid), and still have issues, it's the electronics. (lol)
There are two things I know of that make it turn off suddenly; a warped wheel that makes the steering vibrate, and moving the steering wheel really fast. I really hate the last one.
The box can go bad, and it think that any movement is too much.
Or that you're not going over 15mph.
Or it wont drive the solenoid, etc...
The steering rate sensor is at the bottom of the steering column, under the cover by your knees. It can get really dirty, and have problems reading right. Compressed air will clean it.
Or the solenoid can stick, and have full assist all the time. I'm fairly sure the way the valve is, it can't stick at low assist.
If the rack or fluid is bad enough, the assist will go in and out. Play makes the rate sensor trip the system out.
The Red cougar was doing this just before I replaced the rack, and Lazarus is just starting it.
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
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