I have searched and cannot seem to find a solution.

On my 1990 vert the power steering went out about a week ago. Fluid level was fine and there were no leaks. Pumped seemed to make weird noises, so i got a reman OEM pump and installed it. Pump is now working fine, however still no power steering. There are still no leaks and the fluid level is fine.

With the car in the air, engine off, I can move the wheels lock to lock normally, no binding.

Any ideas?

 

does your speedo work...???

 

nope, but ive got an s5 with the engine speed sensitive PS. does the speed still need to work?

edit: hooked up the speedo cable and PS still doesnt work

 

i think the powesteering receives input from the speedo cable

Jason NYC

 

+1 he is right

 

so on the engine speed sensitive power steering, it still receives input from the speedo cable? are you guys sure about this?

 

two hoses on the power steering pump, or three?

 

2 hoses

i did hook up the speedo cable, just in case, but it didnt solve anything.

removed the return line from the pump and started the car to check for flow. everything looked good. refilled the system, blead the air and still no power. thinking of just changing the rack

 

speedo will have no effect on that system. Two hoses= engine speed variable power steering.

Is your trailing coil and tac woriking correctly??

 

yes, trailing coil and tac are working

 

Okay, that rules out the speed signal.

Did you bleed out the power steering system when you installed the new pump?

 

i thought i did. i installed the pump, filled the resevoir with fluid and then turned the wheel lock to lock a couple times. refilled the fluid and went lock to lock again. started the engine and did the same thing, never got any power. even taken it for a drive, hoping that might somehow get it to start working, but nothing at all.

as a note, when it died a week ago, it went out intermittently. it would stop working then suddenly work again and this went on for a day until it just completely stopped working.

i appreciate the help so far, thanks

 

I normally use a seperate container for the return when bleeding as sometimes it will bubble and get air back in the lines if you just use the stock resevoir.

But from your description it may be more likely a bad power steering CPU. The problem is, you need one for the engine speed sensing steering which was really on very few cars.

I would probably next check all my voltages at both the power steering CPU and the pump. The shop manual shows what they should be. You will need a multi-meter to check them though. You could also do it the Mazda dealer tech way, and just replace the Power Steering CPU, but check the power at least first at the power steering CPU to make sure you don't have a blown fuse or broken/disconnected wire.

 

i dont believe there is a power steering cpu. i thought this only came on the vehicle speed sensitive systems. i checked the fsm as well.

 

Mazda started phaseing in engine speed sensing steering on the 89 models as a cost cutting measure. At first it was just the base GTU model, but by the end of the S5 models it was on all the non turbos.

Two line power steering pump = engine speed sensing power steering
Three line power steering pump = vehicle speed sensing power steering

The former intermittent issue suggests electrical, or air in the lines and rack.

If you look at the 90 model brochure, you will find only the Turbo in 90 had vehicle speed sensing steering. All others had the cheapo cost cutting engine speed sensing power steering:;

 

so are there any electronics associated with the 2-line pump (engine speed sensing)? besides the pressure sensor,i do not see any in the fsm.

 

I don't know. I run away from S5 cars.

But there needs to be some sort of a controller, either built into the pump or out board

 

What about cars that only have 1 power steering line at the PS pump, and no wires coming from the pump / reservoir? My steering is very hard too. Any ideas on why?

 

not exactly sure what is wrong with yours, however i did eventually fix mine. its the same on you have (no wires but has 2 lines total - 1 to the rack and 1 return). i fixed mine by just replacing the whole rack, i think it was associated with the amount of steering angle spacers i was using. after i replaced the rack it broke again on the next drift day. took out the huge amount of spacers and no more broken racks.

 

I have a 89 GTU where the original power steering was removed when I bought the car from my friend. I now have a JDM S5 Tii swap, and I was wondering if I could make the power steering that came with the turbo engine work with my GTU. (i'm using the N/A harness)