MX5 NC Sporadic Heavy Steering

[SafeTrisK]

Just thought I'd give an update on the issue. I've been trying my hardest to ignore it over the summer and drive due to the great weather.

The steering feel has continued to be sporadic. But I have noticed things which may be leading to something to do with the brakes.

Ive noticed that the front N/S alloy wheel is becoming more contaminated with brake dust than the other side, also I've noticed a slight pull to the left particularly under light braking. Leading me to think the front N/S brake is binding slightly. The caliper was replaced for a refurbed unit 21 months (14,000 miles) ago and all front slider pins were replaced and greased only 4 months ago. The front N/S disc has a more noticeable lip compared to the opposite side. When raising the front of the vehicle I can't tell any difference when spinning the wheels. By the way no scrapping noise noted for a while.

Both discs and pads have plenty of life left but the pads aren't a particularly good make.

Does anybody else feel that this could be the cause of the steering issues? As I mentioned at the start of this thread that the only time I've felt poor handling similar to this is when the same caliper had seized badly.

Would anybody suggest replacing the caliper again or maybe discs and pads or both as it appears if it is binding its only light as there's no difference in wheel temperature after a long journey.

Cheers.

 

 

[NickT]

A brake hole partially collapsing can give the same effect as a binding brake caliper too.

[Tony]

Reads like the bind is only slight but it worth stripping it all down and make sure nothing is seized.

[Adg]

This is interesting to read im having exactly the same on my mk8 Civic but that has an electric rack as opposed to hydraulic! Ironically i had an NC MX5 aswell and i had something similar where the steering used to go really light for no reason. I never got to the bottom of it sadly but i drove some later models which felt much better so i dont know if it was just a characteristic of the earlier model...Apparently later ones have differebt ARBs?? Shame as aside from that it was a great car and wish i do miss it.

[Tony]

Some cars with ESR have progressive steering weight?..... Put this way.... around town under 30mph the steering is very light. Above 30mph, motorway it adds weight.

[Tony]

Forgot to say.... Mazda wrote a patch for the ND and installed it in 1000 cars to cure the problem, but they're not recalling any other cars?

[Adg]

@SafeTrisKDid you manage to find your issue? Im also having the same still on mine with electric power steering. I wonder if tyres could cause this behaviour as thats all i can narrow it down to but i doubt it. 

[Tony]

Is yours also pulling?

[Adg]

Not as such @Tonybut it definitely feels like the steerings more biased to the left. Feels very numb when turning that side with little self centering and more sensitive to bump steer and road camber that side.

Handling is pretty horrible on mine at the moment however am starting to wonder if its just normal for this car. I know the Type R gets a lot of flak. 

[Tony]

Has the car been lowered.

[Adg]

No but an interesting development - Ive done some heavier braking recently after the OP considering whether it was the brakes binding on their car. It may just be me but it does feel slightly better, also brakes feel sharper too. Noticing sometimes the handbrake feels a tad stiff sometimes so suspecting some possible bind somewhere however there's no excess heat from any wheels. Either that or its Avons I have upfront - I just wonder if they're nor well suited to the car. 

[Tony]

Two ways to test the brakes

1: If the journey with cold brakes and no pulling. After a few miles and then it pulls. This is because when they bind, they also expand.

2: After the journey feel the wheels ( with the back of your hand ) if one is hotter than the other on the same axel this would also suggest a bind.

[Adg]

Okay ive changed the tyres to Goodyear Eagle F1s, great tyres and i thought id solved my problem but after a few days im back to the same behaviour. Actually getting quite unpleasant to drive now. I do think that the right offside front calliper does get slightly hotter but not noticeably so. Checked for a bind on rears too.
Im thinking this might be an EPS issue, i made a different post on this but i do wonder why my car’s steering has a different feel often from day to day. Just interested as to what factors would cause it, either that or electric power steering has odd quirks. Same days it feels more planted some days it feels skatey and wobbly. 
Either that or gremlins are tinkering with my car overnight!!! 

[Tony]

Can you check if one of the brake discs is blued? If one get hot due to a bind then it will overheat the disc. 

[ihs61]

Hi

I have a 2006 MX5 2.0 sport with exactly the same problem as SafeTrisK has described.

The car has done 54,000 miles, I have owned the car for over 5 yrs and only use infrequently

This is what I have checked or fitted over the last 4/5 months

The brakes are not binding

The 4 tyres are matched  premium brands at the correct psi

I have changed the entire fluid not just the reservoir

A new PS drive belt correctly tensioned

A low mileage PS pump and steering rack fitted 

New genuine mazda PS pump pressure switch

With the track rod ends disconnected the wheels turned L&R freely

If i turn the wheels the rpm does not pick up, I have tested the voltage to the switch - 11.67v, 

 

I am at my wits end, any suggestions other than throwing a match under the car ?

Thank you Ian

 

 

 

[Adg]

9 hours ago, Tony said:

Can you check if one of the brake discs is blued? If one get hot due to a bind then it will overheat the disc. 

Hmmm no sign unfortunately. Brakes as cool as a cucumber after a mway drive. Actually cooler than I expected! 
My only other guess with this would be a worn strut/struts of some kind. Ive been told on this model Civic its very unusual for the PAS to play up. 
 

Sorry to hear youre having trouble too @ihs61. Its infuriating isnt it when you have to put up with it on a daily basis. Im sure ive had this problem with another car too but never got to the bottom of it.

[Tony]

Our only reason we've experience with the ND is the steering being too light. We advance the geometry but it made little difference. Mazda wrote a patch to address the complaint but only for 1000 cars. In my opinion there should have been a recall.

It's possible your problem is the EPS... It would be wise to have a plugin to see if there's any error codes?

[ihs61]

Hi

I did have a fault code of P0550 Generic  - current - power steering pressure sensor/switch circuit, I removed the fault code and its still clear

I fitted a new sensor switch plus tested the wire it has 11.67V

When I ground this wire the engine speed should increase but it doesn't, I know this is so low speed manoeuvres can be done with increase engine revs to power the steering - but what else does it do ? could this be the route of my fault, the power steering is working but its not as powerful as it used to be especially noticeable when manoeuvring at low speeds.

I have effectively changed all the mechanical parts of the steering, so what else could it be

Many thanks to all - Ian

 

[Tony]

It's the ECU... They add assistance at low speed for parking and town driving and then the ECU will order weight when driving at speed.

As said Mazda wrote a patch to deal with these issues but only for 1000 cars?

In truth the ND sales have been very low... If i'm honest i didn't like the car because it has overtones from other cars like TVR. But as rude as that sounds i really like the car although it has issues..... Don't be disappointed, Merc, Lexuse, BMW and so on also has issues. 

Other than the raised height of the NC3 we can deal with all the issues but the ND, I'm still on the fence with this one.