I have a 2005 Mazda RX8 with approx 42000 miles. I have exhaust, agency power crank pulley, esmeril racing coil packs and magnacore wires. Recently i had a dvd player installed as well. The past few weeks my cars idle has gotten rougher and rougher. So far we have checked and rechecked the wiring on the coil packs, the plug wires, flushed and changed all fluids, cleaned the trottle body. We had another intake on there, and thought it might be the culprit but it seems its not because we put the stock one back on and still find ourselves having the same issues. It gets worse when you turn the A/C on, but even with it off it's still very noticable. Does anyone have any advice or ran into the same problem and have a fix? I know this car got all the recalls taken care of, i have the documentation. Personally I think one of the coil packs might be faulty but I don't know how to check that.

 

i would switch back to the stock coils and see if that fixes it..

and btw, first post in the right place.. good job..

beers

 

Would love to but the stocks are burnt out. Don't wanna drop some more cash only to find out it's not the coil packs. I did notice the car hasn't had the motor mount recall, going to take it in tuesday to make them do it! If that doesn't fix it, well, then i'll consider buying a new set of stock coils, unless there is a way to test the ones i have on now. Also, the engine wasnt doing this when we first put the coil packs on, had them on a while before this even started. The weather has gotten really hot here, I wonder if that could be a problem. Also, the previous owner barely even drove the car, it had only 30,000 miles on it when i bought in in jan, ive already put 12,000 on it, maybe extra tension caused the motor mount issue?

 

motor mounts make a huge difference in how the car idles..

you dont mention where you are. as to coils, maybe someone local could swap with you..

beers

 

Vegas, sorry. Super hot desert.

 

Did I miss it or.....How many miles on the spark plugs?

 

test resistance of the coils to see if there is something wrong

 

new spark plugs

 

Did you ever find the cause of this problem? I have had the exact same symptoms. I will be replacing the motor mounts soon to see if that helps. I have new coils and plugs also.

Edit: I should add that my car is 100% stock, problem is worse when it's very hot out and A/C makes it terrible. Driving down the freeway for a while in hot weather and then stop in the city and it gets pretty bad.

 

Good place to start is checking the idle vacuum level and engine compression values.

 

motor mounts after all

 

Turn on the car to the engine on position, but do not start it.
Press brake pedal twenty five times.
Your gauges should move when you hit twenty times.

Turn the key off, then restart the car.
How is your idle?

 

My car does the same thing when it really hot outside. Our engine run very hot. With the added heat from outside it doesn't help. What I did to help release heat for engine bay is add 2 spacer under the hood of the car on the back side, near the front windshield. You can get these at a local Autozone. This help out alot. When it really hot out and you're sitting at a light. You could see heat wave coming out of the bay.
Hope this help.

 

Guys thanks but i figured it out and had the problem fixed, turns out it was the motor mounts.

 

Great.... did you do it yourself? What did it cost you aprox...here is the "TSB" and 2005 cars are listed.

http://www.finishlineperformance.com...01-09-2062.pdf

 

Didn't do it myself, dealership did it because i had other problems too, well, my trans, so i wanted it done in one shot, cost me almost 600 bucks, it was explained to me that the tsb is only to help the techs and that the warranty doesnt cover the motor mounts, so, i guess you could say i took one for the team. next time its self install.

 

wow,

i really think that should have been covered under the power train warranty. more so that this is a known problem.

mine were replaced for free with my motor at 56k miles..

beers

 

Did the 06 have the new motor mounts?

 

yes

 

yeah i called corporate because i thought so too but they told me nope

 

i just bought an 04 rx8 it has 77k miles on it and it shakes like crazy exactly on 1k rpm and when i go in reverse. Im almost conviced that its the motor mounts. My question is should i take it to mazda to get them replaced or just buy the mounts (which i was only able to find the right one on ebay) and take it to any shop to have them replaced.

 

The dealer might have more experince.....do you have a Mazda specialist in your area? Get estimates. Glad I got mine done under BB.

 

Any mazda specialist, not that i know of.