Power steering fail & uneven steering force
 

My power steering has been failing from time to time for the past 3 months.

Once a while, there was no power steering when start the car the next day or sometimes even within the same date. The temperory solution to get it back to work is to unplug the negative cable connected to the battery, wait for 20-30 seconds, then plug it back again. When I reconnect the plug, I can hear a flipping souund from the fuse box area, and it sounds like a relay.

Yesterday, I relocated my battery to the trunk. After that, the power steering failed again on the 3rd start. Reconnecting the negative plug fix the problem temperorily but now there is a new problem: uneven steering force between turning left and turning right. Any idea?

Its possible that your new battery cables are too small. The power steering rack actually pulls quite a bit of peak current when it is boosting. If your battery cables are too small then the rack sees a voltage at its terminals that is somewhat dependant on how much power it is trying to pull, which could really mess with the feel. I would recommend using 4/0 battery cable if you are doing a trunk mount. Standard 12V battery cable is usually #2, because the run is short from the underhood mount.

On the failure of the rack itself, there is a TSB for one of the connectors that takes care of a corrosion issue, which is probably the cause of your first symptom.

I am using indutrial 2 guage welding cables for both positive and negative.

2 gauge isn't big enough. You need at least 0, preferable 2/0 or 4/0.

and dont use industrial cable, it doesnt flow as much current/has higher resistance per foot when compared to good car audio power wire.

and 2 guage should be adequate, and the cable shouldnt really matter, as when the car is running it gets its power from the alternator, not the battery. the sole purpose of a battery in a car (im not talking about when you have a system or hydraulics) is to start the car.

The alternator can only provide about 90 amps peak at several thousand RPM. The steering rack draws much more than that when boosting, and tends to need the most boost at idle and very low rpm's because the car isn't moving.

I suppose you could test it to see if the rack works better when you rev the engine higher.

In most cars the steering has nothing to do with the battery. The RX-8 has electric power steering, which replaces the hydraulic system.

Update
 

I think I found the problem. A summary of the issue:

Losing power steering occationally after I installed a manual fan switch consisted of 3 relays and a switch. They are wired in the way that when the switch is off, both fans works as stock setup, but with the switch on, both fans operate at full speed.

The problem got worse when I relocated the battery to the trunk. Losing power steering occationally, and even when it is working, the steering force between left turn and right turn is different. The difference in steering force was getting more and more obvious during driving and eventually, would become no power steering at all. The problem was not solved after I put the battery back to the front.

Last weekend, I took out the entire wiring for the manual fan switch and relays, so the fans are back to stock setup. So far, the power steering is working normally. The battery is still in the front.

During the time when the power steering was not working probably, I was able to get it fixed temperorily by disconneting the +ve and the -ve power cable from the EPS module attached directly to the battery, and every time I reconneted them, I could hear a click sound from the fuse box area, that sounds like a relay. However I could not identify which relay was triggered. So far, no blown fuse nor bad relay.

I can't say the problem is fixed permenantly, as there were only less than 10 separate drivings after the fix. I will report any new foundings/issues in the future.

Thanks for everyone for every inputs.

Sammy

Same problem again, no power steering
 

Tonight, when I started the car, no power steering again! I don't know what I can try now, probably I will try to get the new wiring harness for the power steering module. Can someone please let me know what is the part # for the new/revised power steering harness?

Thanks.

Sammy

Go to the dealer I have the same problem since july 2005 nobody fix the problem.

Rx8black, did dealer fix your power steering problem? If they did, what did they do/ what parts did they replace? Mazda voided my warranty 1 year ago, so it would be too expensive for me to bring the car to dealer to fix it, especially when no one know what the problem is.

I had this prob after my 8 was in a wreck. Almost got killed too.
I was doing 40+ it was ranning out and it locked up pulled to the right hard so I pulled to the left and my back end broke lose I was over the dam road. Good thing I was in the center lain and not the inside lain where the palm trees are of that could have been it for me.

I went to the dealer the next day they told me the shop forgot to replace a part that controlls something on the right side and is linked to the power sterring. Thats why it would pull to the right real hard. When it would go out a light would come one and buz.

If I recall right the part was like $1,000.+

They try to void my warranty,but I put them to the court ,they never found the problem.
They changed:
1)Power Steering module
2)Wiring Hardness
3)They proof with other computer
4) 3 racks

And the problem continue

the only thing ive seen cause uneven steering effort was a drive belt that had shredded and wrapped itself around the steering shaft. also, everytime you disconnect and reconnect the battery are you resetting the steering angle sensor? there will be a steering wheel with an exclamation point icon lit up on the dash if it needs to be reset. just have the key on and turn all the way clockwise till it stops, then counter clockwise till stop, then back to center

new findings
 

I did some testing on the circuit/relays and found that, when the power steering is not working, the main (EGI) relay in the fuse box is in "on" position all the time even when the key is removed. I am suspecting that there is a short circuit somewhere, and I will try to find our where it is.

I have had this issue off and on for 2 years now. The first time my car did this they replaced the rack 2 times.

It lasted for about 5 days. I took it back in and the replaced the PS module. This also didn't work. Took it to another dealer and they had it for over a month. When I got it back the PS worked for a few weeks and then started acting up again.

It's really frustrating to have this problem. It has no pattern or regularity. It's totally random.

Can any of you guys tell me if this problem with the steering wheel has been fixed I just bought mine a month ago and now its doing the same thing you guys are talking about with the steering wheel. Its been in the shop more than I am driving it. They replaced the rack again and ps module and it still does the same thing!!! Please reply Thanks

Update
 

My power steering has been back to work for a month now. Here are what I did:

I pulled out the eps module, disconnected all eps connectors, took out the battery, disconnected the 2 connectors to the alternator/generator, took out my turbo timer, check continuity on all eps harnesses, and they are all good.

Found loose bolts on the turbo inlet pipe, and loose screws on the MAF sensor. That explain why the car had really bad idle which caused the voltage dropped from 14.4V to below 12V.

Put everything back together (except the turbo timer) and reconnected all connectors. It has been working from that point.

I suspect the eps failure was casued by the dropping of voltage which was cased by the loose bolts/intake leaks. Hence for people whose eps has similar problem and idle badly may try to check the voltage to see if there is any fluctuation, and/or any intake/vacuum leaks.

hey sammy u said in an earlier post that a a relay is on all the time..........i wouldnt necessarily say its a short, but its wiring is probably cross shorted on another wire thats hot all the time...........like maybe its cross shorted on the hot wire to one of ur lights or something.........best bet get urself a wiring diagram for the rx8..........

if it's a cross short situation, then it should be still on all the time now, but all relays are working properly now.

one interesting note: with the key removed, when i disconnect the ground wire for the radio, it (the radio) will turn on; when i connect the ground wire back again, it will turn off.

i too have powersteering issues i pull the eps fuse and put it back in and that seems to work. MAZDA dealer wants to charge 1000 dollars to fix instead of troubleshooting which i think is my best bet after reading everything on this forum.

Sensor
 

Has the steering angle sensor been replaced ?

well every morning i warm up the engine shut it down and then pull the eps fuse on the battery connection, put it back in restart the car and the power steering stays on until of course the next time i shut it off (sometimes) or the next morning. where is the steering angle sensor and if possible can i get one and replace it myself thanks for the help

Well now it seems that my power steering has failed and does not want to return anyways i bought this wehicle in for a recall and conveniently the power steering failed the day after i got it back they said what they did had nothing to do with it i said BullS*^t and took my car out of there before they fcukd anything else up anyway it would cost a 1000 dollars to fix because my car is out of warranty. But am i the only one that looks past all these problems and does not want to give up on this car even though it sucks down gas and oil like cheap vodka. i just love roastin people with it and its handling is unparalleled by anything i have ever driven. Well i will see if i can get the steering fixed at least you can still drive it without powersteering and frankly i am used to it now just a little tricky parking it but thats it.

i got the same prob with power steering going soft and hard, i will try get some one to clean the terminals and tourq senser,, if i go on a long journey i will go to the trouble of puting key in ingnition and put in on position and turn the steering wheel left full lock to right full lock 3 times and start the engine,, this works every time but when you switch the engine off likely that it has gone stiff again when you start it back up