Hi Folks --
I have a 2004 RX8 6Spd with less than 30,000 mi.
I took it in to dealer because it started sputtering and dealer wants $1600 to change coils and plugs. I had this done on 2019 and only drove it a may 2-3K miles and dealer says the lack of driving would cause coils and plugs to deteriorate. The thing is I had a little Nissan pickup that also hardly drove and that thing would start at any time, under any conditions, no matter how long I let it sit.
Any advice on the dealer diagnosis you can offer would be appreciated.

 

Probably has more to do with old gas if anything. Try siphoning and replacing the gas with fresh shell Vpower first. The original coils do tend to die early, but if you had replaced them and intermittently drove they should be fine.

Coils and plugs don't really degrade, they would just corrode on exposed connections if anything. To change spark plugs you need a socket and ratchet set and a floor jack.
A new set of plugs is 120$
A new set of Rev C coils (N3H1-18-100B-9U) is 400$
A set of 10mm magnecor wires is about 120$
So parts alone are 640. With the other 1000 you could buy a socket set for 50-100$ and spend a few hours turning a wrench to do it right. I would not ever leave a car like this in a dealership's hands. You are trusting some random 20yo tech kid with your niche car/engine and paying them an obscene price.

 

Fresh fuel, clean airflow sensor, and start hunting for vacuum leaks. Unlikely to be your ignition components in this situation, in my opinion anyways.

 

Many Thanks! ... I'll give it a whirl with the plugs and wires to start and see where that takes me. I'll circle back with lessons learned.

Cheers!

 

Wait, what? Unless you left it out in the rain for 6 years, the coils and plugs haven't deteriorated. 1600 is insanely expensive for those parts, please don't encourage the dealer to throw parts at the problem without proper diagnosis. Coils can be tested, it's in the Mazda shop manual.

When you say it's sputtering, what do you mean? What other possible causes has the dealer tested and eliminated?

 

I would be interested in the fuel pump going bad, clogged injector, old bad fuel, did they test anything?
obd2 have any codes?
did they clean the air flow meter?

 

I wanted to ask if you removed and inspected the plugs and coils and see what the results were. I wasn't sure if you were doing that yourself or if the dealership was performing the inspection or replacement. $1600 is extremely expensive for this repair, especially if they offered no other diagnosis or even asked for more time to look into the issue. We just want to make sure you aren't being taken advantage of is all.

 

Yes, I ended up taking it to a mom & pop shop I've used before. He got misfire codes and replaced coils, plugs, and plug cables, all for less than $900, almost $700 of that was parts. Engine light off and runs great. He explained ignition system on these rotaries do have issues, especially if not driven enough ... and that all three should be replaced together or *** nay be hit or miss. Plugs were pretty corroded. Thanks for all the feedback folks. Hope this helps. Zoom Zoom still a thing?