Mark

After 450 miles, 19mpg, the car has developed a significant pull to the right or left when braking on bumpy or irregular pavement. The steering wheel turns a full quarter under these conditions. This occurs at low speed when coming to a traffic light or on the freeway when braking in a turn bay with uneven pavement (very scary which required quick correction). The sterring wheel turns right or left depending on the pavement and is very reproduceable. THIS NEVER OCCURS ON SMOOTH PAVEMENT. It acts exactly like a sticking caliper when it occurs, but only on bumpy pavement (NOT POTHOLES) which makes no sense if it is a caliper. On occasion I have been FULLY stopped and pump the brake pedal and the steering wheel will continue to jerk in the direction it was turning under braking while moving. THE ABS HAS NEVER ACTIVATED. There is no activity from the rear end, all of the action is in the turning of the steering wheel. THE BRAKES AND STEERING ARE OTHERWISE PERFECT UNDER ALL OTHER CIRCUMSTANCES. The steering is unaffected by the uneven pavement as long as I don't hit the brakes. It is due for service and the phone diagnosis from the dealer is "it's probably the pavement".

zoom44

mine has started to do this also. it started just after 1000 miles in mine and does not seem to be as severe as yours, i.e not a quarter turn of the wheel but about half of that. i thought at first that is the brakes pulling as it was always to the right but as time goes on i see now that it pulls left or right but had not equated it to the bumpy pavement until you mentioned it. i think now though that it is almost always on bumpy pavement. i can also when it is occuring stop at a light and pump the brake and it will pull still in the direction it was while moving. i have noticed, just last night wheni wasn't accelerating but just moving at a steady speed on a certain stretch of the highway i drive home on, and it was definetly to the left then but at the end of the off ramp while braking it was to the right. no abs activation for me either at least that i noticed. since mine is not as drastic right now that yours seems to be, i will wait until i have mine checked once i have the free service in hand so i can have it checked when i take it in for the oil change.unless it gets worse that is. keep me posted on what you find out. and thanks for posting it up here.

mikeb

that stinks. are you guys going to take the car to the dealer for service. keep us posted

compaddict

Sounds normal for a sports car. The more you isolate the steering wheel from the car the less pulling you get at low speed. It really is a good thing!

Vince

dcfc3s

Make sure the air pressure in all your tires is correct (32 psi) - you can get all kinds of funky response with high or low air pressure.

Might also want to try driving with the traction control system totally disabled and see if that makes a difference.

Dale

zoom44

nahh vince this is definetly not a good thing. i really don't like wrestling with the steering wheel at freeway speeds to keep the car going where i intend it to. and it is a definite change from how it was before. like i said it feels like the breaks are pulling the car to one side or like bad torque steer on a front wheel drive. but not always to the same side.

rx8daniel

I've just noticed this in the past few days also. Although in the car's defense, some of these occasions have been on poorly crowned or very uneven road surfaces. I'll be watching mine to see if it continues. It's at home in the garage today - testing resumes tomorrow at 6AM.

Mark

Make sure the air pressure in all your tires is correct (32 psi) - you can get all kinds of funky response with high or low air pressure.

Might also want to try driving with the traction control system totally disabled and see if that makes a difference.

Dale
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I forgot to mention the tire pressure is spot on 32psi in all four tires. I have not tried to turn off the DSC/trac but I may need the dsc if i hit the brakes on uneven freeway again!. My brother has an 01 Vette which follows grooves and ruts in the freeway which is expected in a fat tire sports car. The 8 tracks beautifully, it is only when you brake on the bumps is there a problem.

I'll try the DSC off and if it goes away then i'll know that the defect is in this system. I have little to no faith in the local yocal service dept. I will send Mazda USA a letter re this defect. Given the response of others, this is not isolated to my car.YOU HEARD IT HERE FIRST, MAZDA WILL RECALL THE RX8 FOR THIS DEFECT. When this happens you'll think, that guy was right!

Velocity red, r/b,gt 6spd, 6disc. 492 miles.

Mark

nahh vince this is definetly not a good thing. i really don't like wrestling with the steering wheel at freeway speeds to keep the car going where i intend it to. and it is a definite change from how it was before. like i said it feels like the breaks are pulling the car to one side or like bad torque steer on a front wheel drive. but not always to the same side.
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Amen brother, bad torque steer or a variably intermittent stuck caliper. At least on my old beaters with a stuck caliper, It was predictable and regular. Wrestling the steering wheel is very accurate. I wonder if it is in the electric steering. I read in a journal that the steering shaft IS the shaft of the electric motor. A first? I don't know what this means. It is dangerous and just started a few days ago. Owner since 8/11

zoom44

i don't think it will be a recall but it should make service bulletin status.

Mark

i don't think it will be a recall but it should make service bulletin status.

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Perhaps.

A TSB is possible, but mine is so bad it could cause loss of control at freeway speeds!

Audi had to recall ALL TTs because of high speed oversteer due to rear lift. That weird rear trunk slope. Notice ALL TTs have a rear spoiler, one of the few that actually reduces lift. Several crashes occured on the Autobahn because of this lack of downforce. I certainly hope no crashes occur to force a recall for the 8. If the problem is only a few cars then a quiet recall (TSB) would indeed happen.

Magnesium

Mine does it slightly too, but being a previous front wheel drive owner, it feels just like road wander when the tires needs to be rotated due to wear on the edges.

Keep your tires rotated and you shouldn't have a problem.

OverLOAD

I've noticed the oversteer problem at low speed also, however I think that in my case, the pulling on the steering is entirely the fault of the road.

How about you find a good road, with nice, heavily worn ruts, and drive it at low speed (~5 mph) and see how the car pulls to each side depending on it's position in the ruts. It's totally normal for a car with this kind of suspension, and tire this wide.

You'll probably notice that the RX-8 feels like it has very solid, precise steering. This particular road feedback happens more often at low speed, due to speed based power steering amplification. At low speeds & rpms, is where the RX-8 is close to the lowest power steering boost...

If you try this out, and still think that it's not related to the road, it's going to be difficult to diagnose, esp if it only happens on bumpy roads.. It could be related to the suspension design, and the camber changing as the suspension length changes from bumps..

OverLOAD

compaddict

Sorry about the confusion I was replying to Mark's post and he was talking about very low speed stuff and I didn't catch the high speed issue.

Sounds very scary, I would leave it at the dealer until fixed.

Vince

Zoom2X

I've noticed this problem also. I first noticed it at about 250 miles on the car. It only seems to occur when coming to a stop on pavement that is rough on only one side. I believe the speed has been below 25 mph but I haven't verified it. The sudden pull of the wheel can be quite alarming although I've had no trouble keeping the car in line.

highspeed8

Count me in on this one too. I thought it odd that the steering would pull a little at <10 mph on slight road imperfections.

zoom44

Overload mentioned speed but also rpms. this does seem to happen more often or perhaps always at low rpms so it could be just suspension design. last night on my ride home i disabled the dsc and tcs. it seemed to me that i did not have the problem as much, i could still feel the wheels try to drive in the road ruts i did not get the heavier tug on the steering wheel that i have experienced before. i am going to try various sections of road with the electronics on and off over the next few days to check if i can replicate that or if it was just a particular stretch of road. could it be that the tcs is reacting to some tire slip or something when in the ruts and is applying brake to one side or the other? again i think Overloads point of low rpms is a key here. that piece of road i checked out last night i am usually in 6th at like 55-60 mph.

OverLOAD

It was the same with my MX-3 GS.. At low RPM's the wheels would drift around more, esp when at low speed. When rolling to a stop in nuetral, the wheels really pulled into the ruts..

As for at 55 - 60 mpg in 6th.. that's about 2750 to 3000 rpms.. unless the road has some crazy grooves, or is sharply angled down, it shouldn't really pull at all.. What's the road like?

OverLOAD

zoom44

well here in the Portland Oregon area most of the Highways have some pretty large ruts from people who drive around with their damn studded tires 6 months of the year. all in preperation for the 2 inches of snow we get twice a winter here. some areas are worse than others depending on when they were last paved but 90% of them are bigger than any ruts on the roads in the Northeast that i remember from 30 years of living in southeastern PA. i swear the salt used around Philly and surrounding counties is not nearly as harsh on the roads as the studs are. These ruts are usually a couple inches or more deep and hold water long enough for it to freeze in the colder parts of the winter, causing nice long stripes of ice in the lanes where you would normally drive. i hate studded tires

rotarymotory

I think I'd start by having the module that controls the brake force distribution replaced.

It might be interacting with the Traction Control in an unfriendly way. It can't be torque steer (not on a front driver) or bump steer(ABS requires nuetral scrub radius), your tires seem okay, and I can't believe there's a power steering feedback loop that could override your hands (God, let's hope not). I'm left with brake force distribution.

Switch a new module in and out to isolate the solution.

BTW, my 8 doesn't do this. So far everything is A-OK. I love my 8.

RM

Mark

I think I'd start by having the module that controls the brake force distribution replaced.

It might be interacting with the Traction Control in an unfriendly way. It can't be torque steer (not on a front driver) or bump steer(ABS requires nuetral scrub radius), your tires seem okay, and I can't believe there's a power steering feedback loop that could override your hands (God, let's hope not). I'm left with brake force distribution.

Switch a new module in and out to isolate the solution

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You may be on to something here, my original problem is not following ruts or tramlinning. The steering wheel forcibly turns while braking on irregular pavement (EVEN WHILE STOPPED, THE WHEEL WILL PULL IF I PUMP THE BRAKES AFTER ONE OF THESE EPISODES). The wheel does not pull while stopped unless it pulled during a low speed stop. Today I tried with dsc off and got the SOS. I'll mention your suggestion to the service dept. Thanks.

Hayseed

Happens to me. About a 1/4 turn of the steering wheel, in either direction. Only when I'm coming to a stop. Doesn't take a *very* bumpy road. While it was alarming, it didn't feel unsafe, since it happens only at very low speed.

Is this something I should be worrying about???

OverLOAD

Mark:

That sounds like you got major problems. Bring it to a shop you trust, and get them to experience it. That shouldn't ever happen. Get them to do the warranty stuff

Zoom44:

I've seen some pretty bad ruts all around the US and Canada. It's generally something you have to get used to . I never had the wheel pull so hard that I couldn't resist it, but sometimes it's really surprised me by jumping in my hands. The best recommendation is to keep a good solid 10 - 2 grip on the wheel. I don't like the feeling either, but the only way I know to eliminate that is with little wheels, and we don't want that..

OverLOAD

ezradg

I noticed this problem during low speed breaking on a pretty flat road during a test drive. I thought it was a problem with that specific car, as the dealer has designated it as the test-drive vehicle. Hence, all of us have been beating on it pretty hard.

I take delivery Monday, and will watch out for this...

Thanks for the informative post.

TerenceT

mark
how about trying to engage the ABS?

try on a straight road, go up to about 50 and hit the brake, until ABS kicks in WHILE HOLDING THE STEERING STRAIGHT

from reading your post, i am not sure if you meant the car pulled due to the steering wheel turning or because of braking, hence holding your steering wheel straight.

if your calipers are binding, it should be pulling to one side when the abs is engaged on a straight road.

also, the 8's steering is quite sensative and if your steering has turned a quater, the pulling might just be you turning.