Yeah just watched the same video and was about to post the same thing. Looking at the layout it certainly seems like it would load the steering. The only way I can see to stop the arm forces affecting the steering would be to connect the arb via one of the wishbones. This is how arbs are connected on NA mx5s
GR Yaris POWER STEERING FAILS mid turn on the Nürburgring
- Thread starter Dragos_DreS
- Start date
Yeah just watched the same video and was about to post the same thing. Looking at the layout it certainly seems like it would load the steering. The only way I can see to stop the arm forces affecting the steering would be to connect the arb via one of the wishbones. This is how arbs are connected on NA mx5s
HRNSHN-Racing
Fascinated Member
Yes it is. Yes we nearly died
. A friend of mine did a very deep look into the kinematics of the car. It’s all in german and I don’t know how good the translation is. And it’s about one hours of hard and deep talk and very technicalCan confirm it happening on Grobnik, hot day around 32-33, 4 laps in. Stock tyres, dampers and springs, 7 deg caster, -2.5 camber, 1mm toe out total. Started happening as I started driving "wild and unprecise", clean and tidy driving may help in prevention.
I was at the ring again and now with some updates to the car, and this time I never experienced the powersteering fail/lockup.
The updates were: Lithium battery-16Ah-1000 CCA, complete brake cooling kit and shims from hrnshn-racing, ATE 200 brake fluid.
The added brake cooling made a difference in the sense that I didn't have to brake longer then "expected", so no longer that "brake some more"-feeling you get when your brakes are too warm and sometimes/suddenly fades.
The small Lithium battery (2,65kg) did ok, but I hade to get used to always push away the start/stop-function. You can monitor the battery with an app, and after the trip I could see that the state-of-charge had dropped but not the voltage level. While away the SOC was never so low that I had to take pre-cautionary steps like starting the car with a jumpstarter but I choose to maintain when I got home. You don't want your li-battery to cut out.
The updates were: Lithium battery-16Ah-1000 CCA, complete brake cooling kit and shims from hrnshn-racing, ATE 200 brake fluid.
The added brake cooling made a difference in the sense that I didn't have to brake longer then "expected", so no longer that "brake some more"-feeling you get when your brakes are too warm and sometimes/suddenly fades.
The small Lithium battery (2,65kg) did ok, but I hade to get used to always push away the start/stop-function. You can monitor the battery with an app, and after the trip I could see that the state-of-charge had dropped but not the voltage level. While away the SOC was never so low that I had to take pre-cautionary steps like starting the car with a jumpstarter but I choose to maintain when I got home. You don't want your li-battery to cut out.
There is also a competition 4WD controller available directly from Toyota with the part no. 89630 – 52190
Aftermarketlink: https://easycars.jp/product/toyota-genuine-competition-4wd-control-ecu-for-gr-yaris/
Similar approach like Syvecs, Kotouc but with a pre-selected approach:
Competition 4WD control ECU developed with professional drivers for each stage of tarmac and gravel. When sport mode is selected, it is for rally tarmac stages and gymkhana mini circuits, and when track mode is selected, it is for rally gravel stages and dirt trials.
Aftermarketlink: https://easycars.jp/product/toyota-genuine-competition-4wd-control-ecu-for-gr-yaris/
Similar approach like Syvecs, Kotouc but with a pre-selected approach:
Product features
Competition 4WD control ECU developed with professional drivers for each stage of tarmac and gravel. When sport mode is selected, it is for rally tarmac stages and gymkhana mini circuits, and when track mode is selected, it is for rally gravel stages and dirt trials.
sixtentouge
Totally Hooked
- Aug 28, 2023
- 202
- 801
- 128
Also, Toyota considers this a motorsport part, and installing it voids the powertrain warranty.
Michael Knight
Totally Hooked
would be nice to hear what is the Toyota warranty in terms of their extended warranty program, given the clutch isn't part of that, and assuming neither are the CV joints. well, maybe the unserviceable center clutch pack could be one of those, if one manages to kill one?
Nixkf
Dedicated member
- Dec 16, 2021
- 138
- 173
- 43
Would be nice to weigh up the costs of mandatory services from Toyota vs. doing it myself and keep the saved money in an savings account once something breaks to pay for it since warranty seems to be quite often denied for silly reasons. The car is not ment to be kept stock in my opinion so every mod will void a certain area which is only covered keeping the car stock... Could also be a self-serving bias to justify spendings..
Ive chatted briefly with 55parts and they have already upgraded the stock 4WD Controller to an aftermarket one. Will be interesting to see if it helps with the steering issues.
I had no issues so far with the steering but my car is stock so far. However, i bought the german WRC Triple Edition which comes with an optional tuning package from Toyota (similar to the Kinto package in Japan) which alters the track mode to a progressive 45:55 distribution.
Will follow up once the car gets used in the next season.
Ive chatted briefly with 55parts and they have already upgraded the stock 4WD Controller to an aftermarket one. Will be interesting to see if it helps with the steering issues.
Nixkf:
It will change the 4WD Distribution to be more suited for the mentioned gravel and tarmac tracks.I had no issues so far with the steering but my car is stock so far. However, i bought the german WRC Triple Edition which comes with an optional tuning package from Toyota (similar to the Kinto package in Japan) which alters the track mode to a progressive 45:55 distribution.
Will follow up once the car gets used in the next season.
Last edited:
Hey, do you have a lithium battery? some have reported this helps with the isuue. I also have the wiborg arms and 9.5'' weds wheels, caster is about 7° with top camber platesMy car was off the road for about 6 months during which time I had the Wiborg arms fitted, and I've only been out once since then, so I don't know if I can really give honest back-to-back feedback on how much difference they made. The car is fantastic to drive - super neutral, will 4-wheel drift under power, very predictable and confidence inspiring, but it was like that before too
I do have some clearance issues with the inside of the wheels rubbing on the arms at full lock, but that might be related to mega (-4/5 deg) camber and/or slightly loo low ride height, I haven't really looked in detail.
I haven't driven the same tracks with/without Wiborg, but I wouldn't say there's a huge difference in encountering the EPAS issue, trailing the brake will pretty much make it happen with or without Wiborg. This is with 255 A052 tyres on a 9" wheel - I didn't encounter it with OEM wheels/tyres, but only did one track day like that.
I would be surprised if it was fixed in the mk2, but you never know. There was a comment above about disconnecting the front ARB making it go away - I'm not super keen on changing the F:R balance, but it would be interesting to see if it does "fix" the problem.
No, I might try that at some point. I do have the syvecs AWD controller, which didn’t make any difference.
Michael Knight
Totally Hooked
Michael Knight
Totally Hooked
I got the power steering loss one day when was driving in city and parked the car wheels in full lock position.
When started the car and started turning the wheel, steering felt very heavy first 0.5-1s or so. Wish it would get worse so would get actual fix from Toyota.
When started the car and started turning the wheel, steering felt very heavy first 0.5-1s or so. Wish it would get worse so would get actual fix from Toyota.
Any updates on this? I suffer with this on track, Spa is terrible for it. With the 2026 updates foe the GR and I think aero pack cars toyota look to have updated the eps torque sensor and new software. Wonder if we can get the software update or if its a whole column along with update as im pretty sure its all one unit..
Last edited:
