Hi, i had my Rx8's spark plugs replaced in January. Recently i started getting problems with my engine so i took it to mazda for a check up(engine management and intercooler light came on), what they had told me was that my ignition coils on bank 1 and 2 were not working properly so i will have to replace them which would cost me £250.

I had bought the full set of ignition coils from fluidmotorsports.com and had them fitted on. The car still showed the engine and intercooler light so i took it back to mazda the next day and had it checked again, this time round what they said was that one of the new ignition coil is misfiring which damaged the spark plug therefore the engine management light is still on.

What Mazda are recommending to me now is that i buy new HT leads and spark plugs to solve this problem which would cost me £430 and not new ignition coils.

What i wanted to know is that do new ignition coils damage the spark plugs requiring me to buy new set of HT leads and plugs or was it that the original plugs that were fitted in January were defective wearing them out within 9 months?

Another thing i noticed in my RX8 was that i had a 430Ah battery inside, its smaller then the battery casing so im not sure if it is the right power for my car. Also can someone tell me if having a smaller battery power causes flooding to happen on the RX8 or not?

Thank You

Considering all the quid you're looking to throw at this (or rather being forced to throw at this), you'd be better off with the BHR ignition system.

But to your questions, yes, improper high voltage off the coils could cause 'plug misfire and adverse wear.

And yes, a lower capacity battery may not be providing the proper voltage to the coils, which in turn are unable to properly transform it .....

And don't forget that 'plug cables can become electrically porus over time and lead to cross/misfires.

It's all related.

Thanks a lot man, really appreciate it.

But close to 800 USD is crap :) The wires are $70 and the Plugs are about $80...and about 1 hr max labor...

You figure it out :) I say they have you bent way over :lol:

When did Mazda add an intercooler? I think you're referring to the low coolant light, it's a radiator not intercooler. What codes did the dealer pull?

The solution

The solution

those look crazy dude!

where can i buy them from and how much does it cost?

PM Charles R. Hill or one of the other Black Halo Racing (BHR) Gents here for build slot availability and pricing/shipping.

GMC Yukon coils mated to MSD cables with a well designed proprietary interface. Very powerful and very reliable. Pretty straightforward to install thanks to its mounting plate (as with everything in the 8's engine bay a bit cramped to work, but do-able).

Mazda did very well on most of the 8's sytems and there's not much room for improvement, e.g. intake, exhaust and brakes, but they underdesigned the ignition system. BHR's system is far better than stock.