zynger

I need to replace the spark plugs on my rx8. and i just so happen to be a poor college student who cant afford all 4 up front, would it harm the performance to replace two plugs now and two more next paycheck time?

wcs

iTrader: (2)

Wow, so I won't go on about how this is likely the worst car in the world for a person on a tight budget.

I will ask why you think you need new plugs?
And why not just wait till you can buy 4?

To answer your question:
No it will not harm the performance.

BigCajun

iTrader: (1)

It's recommended that plugs, coils, and wires be changed together every 30k miles.
In your situation, if you are having misfires, your best bet would be to check to see if your coils are firing.
If you don't know how, or can't afford to get them checked, pull your plugs, see which ones are fouled, and replace the corresponding coils first and try to clean the plugs.
New plugs will be wasted if the coils are not firing.

wcs

iTrader: (2)

I've never had any luck at this, especially with our plugs as they have a iridium coating.

How BC do you "clean" them? Really I'm asking.

BigCajun

iTrader: (1)

I always buy new ones, but I have seen threads where people have cleaned them.
There may even be a DIY on it, I'm not sure.
I believe if the electrodes were soaked in solvent or sprayed with PB Blaster and brushed with a brass or nylon brush, (looks like a toothbrush) that might work.

I say this only for the OP's benefit, given his financial constraints.
We still don't know why he 'needs' new plugs.
I am of the opinion that if he is having misfires, his money would definitely be better spent on coils, which are the usual culprits, and take a chance on trying to clean his plugs.

zynger

The previous owner wasnt the best with mantience and it has 115k without change of plugs. is there a place to get the whole plug, coil and wiring set for reasonably cheap?

wcs

iTrader: (2)

Thanks

ouimetnick

If you get the coils super cheap from somewhere like eBay, they are probably fakes. Real genuine parts will cost you, but they work. Don't skimp on ignition components. If you really can't afford those things, perhaps the RX-8 isn't the right car for you.

wcs

iTrader: (2)

No.
I'm not being a dick
No.

Sorry .. just no

(clearly cheap is a relative term but no ... just no)

wcs

iTrader: (2)

Here this is a good deal
MAZMART - Serving The Mazda Community Since 1980. RX8 RX-8 Tune Up Kit air filter oil filter coils plugs wires OEM NGK spark plugs1


No really I'm serious

BigCajun

iTrader: (1)

Have you had issues, CELs, performance, or other problems? Honestly, I'm surprised the car even runs with that many miles on the plugs.

Steve Dallas

You really do need to replace the entire ignition in a car that age. Auto Parts Warehouse and other similar sites often have 20% off with free shipping coupon codes available, which makes it more bearable, but still not cheap. I get my plugs from APW for under $50 shipped, for example. Click here and here.

Coils and wires can be from any auto parts store. They are fine. Just stay away from the cheap eBay coils. Plugs need to be OEM NGK. You can replace things piecemeal if you need to. Start with the plugs, because their condition will tell you which coil(s) needs attention first.

zynger

The only issue i have now is bad engine mounts, i have the parts and im gonna be replacing them this week. it has a rough idle at times, i cleaned the MAF and throttle body, the last thing i believe it could be is the engine mounts.

gwilliams6

Like everyone else says, you are way way over the limit for those coils, wires and plugs. You need to change all three ASAP, or else you will just ruin any new plugs. Unless your car has BHR coils (which can last the lifetime of your RX8), your coils started giving you less spark and voltage, and less hp around 30,000 miles. Plugs should be changed every 10,000 to 15,000 miles, depending on your driving habits.

Operating on two new plugs and two plugs with 115k miles on them is a very bad idea, as the spark and voltage will be giving you different combustion efficiency in the different rotors (if you put new ones into one rotor only) or uneven combustion (if you put one new plug into each rotor). And unless you are familiar with a rotary engine's combustion, you are unaware that the leading and trailing plugs perform different jobs and that is why the leading and trailing plugs are different with different characteristics. So which two plugs were you going to replace anyway?

Do the right thing and change all four plugs at the same time. Use only OEM NGK's which you can get at most national chain Auto stores for reasonable price. Borrow the money if you have to, but change all plugs with new at the same time if you don't want to further hurt your engine,catalytic converter, and also harm performance. Coils are a little more. See the following link and scroll down to the "Importance of Ignition Health" and read up.

https://www.rx8club.com/new-member-f...4/#post4533701