Blooper4000

So I bought my 04 Rx8 about 2 months ago from a pretty trust worthy dude, I had it inspected before I bought it and everything looked good. Recently I have had several problems with the car. I have a fairly rough idle so I cleaned the MAF sensor which improved the idle a little but it is still a little shakey and it has also stalled several times while at idle. (It seems to stall when hot or when it has been idling for a little while, the needle will dip down below 750 then catch itself and jump back up several times and then finnaly die). Everything seems to act up the lower i get on gas, recently i have been keeping it above half a tank and havent really had any of these symptoms other than the shakey idle but no stalling or dipping of the needle. On top of all this i have god awful gas mileage and on 2 seperate occasions the car has died while driving. It has a little trouble hot starting but cold starts well. The dude i bought it from said the engine was replaced about a year before i bought it and he didnt drive it alot after that but they didnt reset the miles so i do not know exactly how many are on the "new" engine. I do try to redline several times a week and use premuim gas i have also been topping off the oil occasionally. Im hoping that because the engine was supoosedly replaced recently that its not the apex seals but i could use some input from the pros on here. Its my first car i bought so im a little worried, thanks in advance!

200.mph

iTrader: (9)

first off read the new owners threads about 10 times.

mileage on the car? mileage on ignition parts? does it have a cat? clean and reset ess. whats your fuel pressure? i guess you failed to get a rotary specific compression test before you bought it.

read the new owners thread

gwilliams6

https://www.rx8club.com/new-member-f...t-here-202454/

Rouge_rotor

I also have had problems with hot starts, and just cleaned out my MAF over the last weekend because I went through some water. Mine has never stalled on me or even close to doing so but i do know that a possible cause of the troubled hot starts can be caused by failing ignition coils. The OEM coils seem to fail more often than other cars. You should pull the ignition coils and look for white burn marks on the back. This is a sign your coils are failing. Do you have any CEL? There are some good DIY threads on here that explain how to change your coils, pretty simple.

Loki

iTrader: (1)

All good points, except the white marks mean nothing. I would just replace the coils if they're of unkown age or close to 30k miles. Terrible gas mileage is another indicator they're not OK. Don't wait or drive AT ALL until coils, spark plugs and wires are replaced or confirmed good, or you will be shopping for a new engine. There is no reason to believe they were replaced with the engine.

gwilliams6

Ditto Loki, white spots mean nothing.

You have a number of options for coils:
- The Cheapest option: BWD/Intermotor coils from auto parts stores like Advance Auto. 4 coils, 4 plugs, and 4 wires can be had for around $190-220 total based on whatever promotion is running at the time, shipped to your door for free. They are considered to be the first coil revision and you should expect to need to replace them around 20,000 miles, 30,000 miles max. They often come with a "lifetime warranty" by the auto parts store, which could potentially be leveraged for perpetually new coils.

- The Best Upgrade: The BHR ignition coil upgrade can be had for around $500, which eliminates the need to continue replacing coils periodically, as well as deliverying a significantly stronger spark for minor mileage and power gains. It is a proven kit with top notch customer service supporting it. It includes the wires, you still need to add plugs ($80)

- The For-Sure OEM: Mazmart sells all 4 coils of the latest OEM coil revision (C) for around $250, (just the coils, you still need to add plugs and wires) Supported by top notch customer service. They will likely last longer than 30,000 miles, but we don't have much solid data on how long the latest coil revision will last.

- The Most Expensive option: Buying from a dealer will run you around $300+ for the coils, $500+ for coils, wires and plugs, and if you have them do the install, expect to get a bill for anywhere from $700 to $1,800. You may not get the latest coil revision. Yes, you are getting shafted if you take this option, so bring lube.

- The Highest Risk option: Ebay coils continue to pop up as counterfeit, mislabeled, dead on arrival, and have zero post-purchase support largely. They are the "cheapest" listed price, but when you add that $92 or whatever to the price of anything in the list above from having to do it over again, you can see that they are no longer the cheapest option. Do it right the first time. "Motor King" coils are popping up at an attractive price on Ebay, but are being proven as ineffective, to the point of being unable to get the engine fired. "Mazda" branded coils on ebay are almost always counterfeit. Check the seller's name though, since some of our vendors sell legitimate coils there. The price will be $200+ though. Anything sold as "Mazda OEM" under ~$26 per coil should really be considered as suspect and probably counterfeit.

Be wary of "LSx D585 coil upgrades", as not all D585 coils are created the same, and the standard generic D585 coil is not properly designed internally for the RX-8's ignition needs. They generally "work", but there are anomalies and performance issues that have to be solved, if they can be solved. Definitely NOT a plug and play option, even if it is advertised as "plug and play"

GB: SakeBomb Garage IGN-1A Ignition Coil Kit
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