Paul...

We've got a bit of a problem with my RX8 that the dealer is scratching
his head over.  Thought I could bounce it off the group and see if
anyone here has any ideas.

Background...I took it in last week to have them check the brakes  (felt
like warped rotors...it was) and while test driving it, the mechanic
thought that the clutch didn't feel right either.  So, (from the
invoice), besides the front rotors, front and rear pads and rebuilding
the calipers, he replaced the clutch release collar, cover, clutch  disc,
oil seal and a needle bearing.

I'm very happy with the work they did, and the brakes and the clutch
feel better than new.

But, something new has cropped up. I noticed it the day I picked  the car
up and took it right back to them.

The best description is that it feels like the p-factor in an  aircraft.
When accelerating under load (clutch engaged, going up a hill, or
downshifting to pass, etc...) the car pulls to the left...BUT the
steering wheel doesn't turn! Not even a hair! And I don't have rudders
on that bird to hold it straight! And, when the clutch is  depressed, and
the wheels are just idling, and I accelerate the engine, it doesn't do
it...so it's not really p-factor.<G>

If I do try to correct the pull so the car stays in lane, then release
the clutch to shift, or back off on the accelerator, it will snap back
to the right.  If I don't try to correct it with steering,then on
releasing the load, it simply straightens out in whatever lane it's
in...again, the steering wheel never turns even the slightest  (unless I
tried to correct it, of course, which is why it jumps back to the  right
if I've corrected the drift with the steering).

Even using just the cruise control, taking me out of the equation
completely, as it accelerates to climb a hill, it drifts left,  reaching
the top and easing back on the gas, it straightens out...again the
steering wheel doesn't turn even a hair. If I release the cruise while
it's under load, it jumps back to straight travel...and as always, no
steering wheel turn at all.

The mechanics at Holtz can also get it to do it, and the car spent all
day today getting alignment checked, and rechecked by several  different
mechanics, removing all the parts they installed, reinstalling them,
etc., but they still can't get it to drive correctly.

The dealer's service people are baffled (they also service Audi and
Porsche).  They've never seen this before, and don't know what's  causing
it.  Jason (the mechanic) called a couple of other Mazda shops across
the country and some others out west (in your direction) he knows who
have experience in racing Corvettes, as well as the RX8s and they,  too,
are baffled.

They agree that it is dangerous to drive like this, and have given  me a
Mazda 3 loaner until they figure it out.

Does anyone have an idea what may be the problem, or where else to  look
for an answer?  If I can give them some clues or ideas,  then we might
speed this along.

BTW, the tires are brand new (only about 1000 miles on them), and the
car wasn't doing this before I brought it in last week.

At this point, no suggestion is too ridiculous! <G>

Harley Dixon

Obviously there is something wrong with the electronic
rack and pinion. There is a torque sensor in there that
may have  malfunctioned. It sends data to the steering
computer (EPS) and the EPS then applies the appropriate
amount of polarity and voltage to the rack motor.
The torque sensor or EPS could be getting voltage spikes
from some of the other electrical devices in the
car. Perhaps the grounding wire is loose.

Get the dealer to swap it out and see if that
fixes it.

BTW Harley I will be needing new tires on my RX8.
I understand the ride on the tires you bought is much
better than the stock tires. Tell me again what brand
and size did you buy?

Paul Lamar ...No rotor no motor.

Just a hunch:
Check the actual OD of the pair of  tires on the drive axle.  This
sounds like a tire mismatch problem which causes the diff to falsely
interpret the speed differential between its two outputs , the left
and right drive axles.  It take as a surprisingly small difference
side to side to broadcast a very uneasy effect.
I had the problem at LeMans in a car we were developing.  It wanted
to track side to side at 230mph under full power using up the entire
width of the Mulsanne.  As soon as you backed off,  the car ran
straight as an arrow.  I handed it over to my co-driver,  Mr.
Expendable.  He retired shortly thereafter.

The problem turned out to be the diff.  It would apply power to one
output and then cycle to the other, slowly, causing the car to steer
from the rear.
Your description reminded me of the whole mystery, and since there
was a recent tire change involved,  I throw it out there.

-Reeves


I was thinking while I was eating dinner and it sounds to me like
the torsion bar in the electric rack and pinion between the steering
shaft and the rack is broken or disconnected. It would have
to be broken if the car is steering yet the steering wheel is not
moving.

I suspect the sensor is sending steering
info to the EPS and the EPS is steering the car. Strange but
possible I guess. Steer by wire :)