Using an S5 turbo power steering system in an S4 car.

Max777 · 02-18-2010, 12:12 PM

I have a complete S5 power steering system from a vert that I want to install in my S4 turbo. Mechanically, it all bolts in, however I am worried about the variable power assist for the system.

I do not have the power steering computer or sensors. Can I just bolt the rack on without hooking up the electrical stuff?

The FC has a power steering computer, but the pump only has one stationary sensor attached to it. My S4 does not have a power steering ECU, but because of the single wire system, is the damn thing even necessary?

Please only respond if you have first hand experience with this, or have done this before, I do not speculation and people saying "it might work" when they are not sure.

Thank you,

Max.

JL1RX7 · 02-18-2010, 08:21 PM

I know you can. I think the difference will be the computer hate each other and it might beep all the time. I know I had S4 with a different pump and it just ran in high boost all the time. I just can't remember which one it had since it has been ten years since I owned the car.

djmtsu · 02-18-2010, 08:49 PM

Max, I have the S5 steering computer if you need one.

Max777 · 02-19-2010, 12:38 AM

I have the single wire S5 system that came on the verts, turbo and GXL luxury cars.

What really puzzles me is HOW does the system know how much assist to give, and how does it achieve the end result? As I said, there was only one little sensor hooked up, so what's going on to make it all happen?

@DJ: Well, I'm not sure if the S5 unit plugs into the S4 harness, and then I just got layed off, so i'm a bit short on cash right now. I'll take it for free though!

Roen · 03-05-2010, 11:31 AM

Power steering was one of things that Mazda compeltely fucked up on.

1989
GTU (Base model) - Engine Speed Sensing
Turbo II, GXL, Vert - Vehicle Speed Sensing

1990
GTU, GXL, Vert - Engine Speed Sensing
Turbo II - Vehicle Speed Sensing

1991
Coupe, Convertible - Engine Speed Sensing
Turbo - Vehicle Speed Sensing

Are you sure you have the Vehicle Speed system? Do you have 2 lines or 3 lines coming out of the power steering system?

Max777 · 03-06-2010, 08:27 PM

Well, you know what? I put it in, and it works... perfectly. I dont even have a power steering cpu installed.

If that's "fucked up" then a proper system must be this ungodly steering monster...

I think it's the engine speed sensing system after all. Came out of a 1991 vert.

02-18-2010, 12:12 PM	#1
Max777 Pirate Join Date: Mar 2008 Location: Central IL Posts: 1,323 Rep Power: 19	Using an S5 turbo power steering system in an S4 car. I have a complete S5 power steering system from a vert that I want to install in my S4 turbo. Mechanically, it all bolts in, however I am worried about the variable power assist for the system. I do not have the power steering computer or sensors. Can I just bolt the rack on without hooking up the electrical stuff? The FC has a power steering computer, but the pump only has one stationary sensor attached to it. My S4 does not have a power steering ECU, but because of the single wire system, is the damn thing even necessary? Please only respond if you have first hand experience with this, or have done this before, I do not speculation and people saying "it might work" when they are not sure. Thank you, Max. __________________ Rotaries:They are NOT that complicated!

02-18-2010, 08:49 PM	#3
djmtsu My minds tellin' me no... Join Date: Feb 2008 Location: Murfreesboro, TN Posts: 4,043 Rep Power: 22	Max, I have the S5 steering computer if you need one. __________________ 1976 Mazda Cosmo RX-5 1976 Mazda Cosmo RX-5 2003 Toyota Tundra TRD 2015 Toyota 4Runner SR5

02-19-2010, 12:38 AM	#4
Max777 Pirate Join Date: Mar 2008 Location: Central IL Posts: 1,323 Rep Power: 19	I have the single wire S5 system that came on the verts, turbo and GXL luxury cars. What really puzzles me is HOW does the system know how much assist to give, and how does it achieve the end result? As I said, there was only one little sensor hooked up, so what's going on to make it all happen? @DJ: Well, I'm not sure if the S5 unit plugs into the S4 harness, and then I just got layed off, so i'm a bit short on cash right now. I'll take it for free though! __________________ Rotaries:They are NOT that complicated!

03-06-2010, 08:27 PM	#6
Max777 Pirate Join Date: Mar 2008 Location: Central IL Posts: 1,323 Rep Power: 19	Well, you know what? I put it in, and it works... perfectly. I dont even have a power steering cpu installed. If that's "fucked up" then a proper system must be this ungodly steering monster... I think it's the engine speed sensing system after all. Came out of a 1991 vert. __________________ Rotaries:They are NOT that complicated!

02-18-2010, 08:21 PM	#2
JL1RX7 Rotary Fanatic Join Date: Feb 2008 Location: Front Royal, VA Posts: 487 Rep Power: 18	I know you can. I think the difference will be the computer hate each other and it might beep all the time. I know I had S4 with a different pump and it just ran in high boost all the time. I just can't remember which one it had since it has been ten years since I owned the car.

03-05-2010, 11:31 AM	#5
Roen Evil Club Mod Join Date: Feb 2008 Posts: 183 Rep Power: 18	Power steering was one of things that Mazda compeltely fucked up on. 1989 GTU (Base model) - Engine Speed Sensing Turbo II, GXL, Vert - Vehicle Speed Sensing 1990 GTU, GXL, Vert - Engine Speed Sensing Turbo II - Vehicle Speed Sensing 1991 Coupe, Convertible - Engine Speed Sensing Turbo - Vehicle Speed Sensing Are you sure you have the Vehicle Speed system? Do you have 2 lines or 3 lines coming out of the power steering system?