No power steering - R34 GTT

[RR34GTT]

G'day guys. 

My R34 GTT Neo has developed a problem where it has no power steering assist. 

Now I've covered off on all p/s basics first. No hoses leak, fluids replaced. No air bubbles etc. Still no good. 

Former mechanic replaced power steering pump, still no fix. 

We've even replaced the steering rack itself, still no power steering. 

We've isolated the PS pump and confirm that its working as intended and the head unit solenoid on the right hand side of the rack is working as it should also. We're simply just not getting any steering assist. 

Any ideas?? 

I've done some reading on the forum and read that hicas can cause some issues. The vehicle does not have a hicas lock bar. There has been no hicas light on the dash appearing.

Anything I can check for on the hicas end of things that would prevent power steering working as needed?? 

The car has recently had a turbo upgrade (low mount, standard mani with ext wastage fabbed) that was put in by the mechanic prior to the car having these issues. Anything could have been touched in that install that's prompted these problems? 

I've scouted the forum but found nothing thus far and am simply lost. Appreciate any help! 

[hardsteppa]

To me that says hydraulic issue rather than electronic, but the r34 workshop manual has a section on steering diagnosis - do you have it? If not pm your email and will send u a copy. 

[Kinkstaah]

Do you mean power steering at all, or power steering assist which is speed sensitive?

The latter part needs a vacuum source which a lot of people remove when they upgrade turbos and change piping etc. Is this the case.. or do you have no power steering *AT ALL* which results in a massively heavy wheel, or no speed sensitive steering which makes it more "very heavy everywhere".
 

[RR34GTT]

2 hours ago, hardsteppa said:

To me that says hydraulic issue rather than electronic, but the r34 workshop manual has a section on steering diagnosis - do you have it? If not pm your email and will send u a copy. 

Yep, got a copy of that thank you! Have tested all diagnosis, and it hasn't worked sadly. 

 

30 minutes ago, Kinkstaah said:

Do you mean power steering at all, or power steering assist which is speed sensitive?

The latter part needs a vacuum source which a lot of people remove when they upgrade turbos and change piping etc. Is this the case.. or do you have no power steering *AT ALL* which results in a massively heavy wheel, or no speed sensitive steering which makes it more "very heavy everywhere".
 

No power steering at all. Wheel is very heavy while stationary and at speed, although the faster I go the easier It did get to steer. 

I have just had a turbo upgrade done tho, and the problem has only occurred since said upgrade. Given that I've been through a replacement rack & pump and still having issues, it could be related to this.. 

[GTSBoy]

I have no idea if the same "risk" exists on R34s as on R32s, but a long time ago (on my R32) I had the O2 sensor's heater wire burn up in the loom. It damaged the wire that goes to the power steering (solenoid, I think, on the rack, I think) and I lost PS and it went full heavy.

I mention this because if you have been buggering around with the turbo, then the exhaust & O2 sensor have definitely been moved/bumped/etc and it's possible that you might have damaged the wiring (whether to cause a similar problem to what I had, or just coincidentally managed to bork the PS wiring, assuming the R34 loom is similar to the R32 in what wires are where).

[hardsteppa]

3 hours ago, Kinkstaah said:

Do you mean power steering at all, or power steering assist which is speed sensitive?

The latter part needs a vacuum source which a lot of people remove when they upgrade turbos and change piping etc. Is this the case.. or do you have no power steering *AT ALL* which results in a massively heavy wheel, or no speed sensitive steering which makes it more "very heavy everywhere".
 

Isn't the vac part r32 only, after that is all electronic?

[hardsteppa]

And this has literally just happened to me, during driving...was fine when i started the drive. First glance at PFC sensor check says, no signal from ps solenoid when turning.

[GTSBoy]

1 hour ago, hardsteppa said:

Isn't the vac part r32 only, after that is all electronic?

No vac on R32 PS. That's an R34 thing. Dunno about R33.

The big diff between R32 & R3>2 is the rear rack hydraulic actuation became electric actuation. Plus smarter HICAS electronics.... perhaps. Everything else is just detail differences.

[RR34GTT]

Update - 

P/s reservoir off (again) and inspected. Appears fine. Dummy reservoir fitted, minimal improvement but still not great. Original reservoir returned. 

Steering rack removed, inspected again (appears fine), new tie rods fitted and solenoid inspected. Replacement solenoid fitted. Tested previously and worked well. No improvement. 

Solenoid replaced despite original appearing fine. Replacement works but no improvement on p/s situation. 

As of now, plan its to see what the valve on the alternator does... Steering will shudder during turning (stationary) and pump whines as its trying to relieve under minimal load. 

Hicas has not been touched and there's no indication of hicas related issues. 

Open to suggestions. Next stage is to simply replace all p/s related hoses? 

 

Edited October 24, 2019 by RR34GTT

[RR34GTT]

Just additional comment. Drove the car and there is steering assist when at speed, so there is that. Stationary the car steering shudders and the pump whines. 

[Kinkstaah]

Ahh, I have a 34 so I have the vac line. My car is a long way away from that now, I now have a PS pump from a different motor (LS) all hooked up, and removed the hicas entirely (changed the subframe). I get really heavy but constant steering now which I am OK with.

Point being if I can mutilate everything and still have smooth steering, I would be suspecting this at the power steering side of things as opposed to anything electronic or HICAS'y given my setup works without complication

[RR34GTT]

28 minutes ago, Kinkstaah said:

Point being if I can mutilate everything and still have smooth steering, I would be suspecting this at the power steering side of things as opposed to anything electronic or HICAS'y given my setup works without complication

That's a fair shout. 

At this point our next plan is the hoses etc. 

[hardsteppa]

update on mine - turns out the 2 nozzles on the connector that leads to the banjo fitting had blocked with bits of o-ring. When I rebuilt it last weekend the middle o-ring had fallen apart; I had cleaned the shizz out of everything with washdown and blow out with compressed air, but guess there were some little bits stuck in there that came out when driving. 

[RR34GTT]

Update. 

Hoses are off for inspection and replacement to cover off all bases. 

[RR34GTT]

Update! 

It was the power steering reservoir. 

Despite being removed and inspected (appearing fine with all relevant tests) we removed it again and replaced with a copy reservoir. 

Lo and behold, problem solved. 

 

New reservoir fabricated and to be fitted! 

[GTSBoy]

So what was wrong with the old one?

[hardsteppa]

Indeed...no moving parts in it, so..? What did you find to be the issue with it?

[RR34GTT]

Looks to be a tiny, tiny air leak. 

Seems to be small enough that it wasn't picked up initially but after eliminating everything (several times) it was narrowed down to the reservoir as we replaced it with a dummy one which fixed the issue. 

[DraftySquash]

On 24/10/2019 at 5:30 PM, RR34GTT said:

Stationary the car steering shudders and the pump whines. 

Sorry to reopen an old thread but I’ve been having the exact same feeling as you mentioned. I was tipping up my PS fluid today and noticed that while the car was on and stationary, the steering wheel shudders when I’m doing full lock. It wasn’t exactly on the full lock but maybe about 75% turned in one direction. 
 

although, I also found out today that my power steering valve was broken by the previous owner and it was just glued together 😂 that glue had cracked again so it was leaking air. I’m not sure if that’s what caused it. 

[GTSBoy]

57 minutes ago, DraftySquash said:

that glue had cracked again so it was leaking air. I’m not sure if that’s what caused it

Has no effect on the steering itself. Is for idle control.