hi all

i know 07 has drive by wire gas pedal, with no direct connection to the throttle.

does it also have "drive by wire" power steering? basically, is there direct mechanical link between steering wheel and rack and pinion?

 

Yes. The power steering is all electrical, but the electrical parts just replace the hydraulic system normally found in a power steering system. If the power to the system goes out, you are left with a fairly normal rack and pinion steering, just as with a hydraulic system.

-- Alan

 

thank you, Alan.

honestly, i was hoping for a moment that it's not. roads around here are getting worse and worse, would have been nice to feel less kick-back into the steering wheel.

 

Steering has to be "fail safe". That means, if something fails, the resulting failure mode should be safe. The mechanical components rarely fail. Power steering equipment (pumps or motors, and controllers) are far more likely to fail. Because the power steering equipment is the most likely failure mode, they design these systems so that if the power steering fails, you can still steer well enough to safely stop the car.

Imagine the publicity that would result if fatal crashes started happening because the power-steering just decided to turn left at 70 miles-per-hour.

 

no need to imagine. it's a known thing. Hondas had issues of this nature when they introduced their steer by wire system several years ago. somehow, it did not get hammered into them. i think, most of what happened to the stupid floor mat issues with Toyotas was a well paid countermarketing campaign, not much of an issue itself.

anyhow, so here's a dumm question. if there's no mechanical linkage between gas pedal and pintle valve, how do you drive the car if electricity fails? or there IS a fail proof mechanical linkage?

 

I have a 08 there is a physical rod and U-joint system connecting your wheel to your rack …. Trust me its there it was just in my way while installing my amp and sub box!

 

These days, most 'gas pedals' are really devices that you request the cart's ECU for 'more power'. Makes the task of 'response' easy to simulate with aggressive throttle plate movements. Also makes it easier to run engines at minimum vacuum, which helps with Otto cycle efficiency.

On any 'modern' car, if the ECU packs it in, you're walking - or dialing.

 

An important detail is that the engine is not considered safety critical. If the brakes and steering work, you can stop safely. Once you are stopped, you are considered to be safe, even if you cannot 'go' again.

Having to stop half way across Montana in a blizzard is not considered a safety issue of the car, of course. ;-)

 

Not so sure about that, at least here in california… I had a 2004 elantra which used to stall on me as i took off from stop signs, finally after almost killing me by dying in front of a big rig. I took it back and got my $ back under the lemon law…. Had to go to court for it though and prove my car was unfixable by any reasonable means. Which hyundai lost and I won, $14000 back in the bank on that one.

 

I used to have old Nissan 240SX. One time the alternator failed about some hundred odd miles away from home. I stayed off the breaks and anything electrical as much as I could but with about 2 miles still to go, there was no more juice in battery to power the computer (but enough to power ignition coil), so my car switched to fail safe mode. I could drive about 25-30 MPH max in that mode (without computer controlling the engine) and I made it home safely. But with TCH having electrical power steering, power breaks etc. I doubt they would risk similar fail safety design, even if it could be done in case of some major failure, like I had in Nissan with computer no longer working.