triangleztrianglez

So, obviously i am aware of the fact that rx8's dont have the greatest fuel consumption as other cars.

but i get about 160 KILOMETERS per tank.... i only redline it in first gear maybe twice to three times a day otherwise im being forced to shift at 5k rpms to try and savor fuel.

ive already read threads of the average person getting 250-300kms per tank which is why i'm dumbfounded by my mileage. i just bought the car a month ago and am yet to change the plugs coils and wires but i guess my question is will that really give me an extra 100kms per tank..? already cleaned the MAF sensor and replaced air filter as well as cleaned the intake. didnt really help at all.

paimon.soror

iTrader: (15)

need to know more about your car to be able to direct you properly. year, mileage, condition, etc

Posted From RX8Club.com Android App

triangleztrianglez

2005 GT with 103,000 KILOMETERS

havent gotten a compression test yet. (afraid to

Loki

iTrader: (1)

If they current ones are not producing spark, yes, yes it would. Actually normal around here is 400km to a tank, but if you don't do any highway then could be 350.
I would suggest you not drive until you get that done, as it could lead to other failures.

There is nothing to fear in the compression test. It should have been done before you signed for the car, but it is what it is at this point. Was this a private sale or from a dealer?

triangleztrianglez

it was from a dealer. had so many other 8's fail compression tests that i was looking to buy and just made me broke so i went off the feel and health i presumed the car had. about to buy the NGK ignition kit being as its half the price of the bhr and may have to sell it before i go back to school in september.

Loki

iTrader: (1)

NGK doesn't make coils, and coils are the biggest problem. You can get OEM coils from Autozone or NAPA or the like for not that expensive. Dealer prices will be crazy. But also, since this is a dealer purchase, what kind of warranty did you get? Since it's only been a month, you need to take advantage of the mandatory warranties. Where are you from?

triangleztrianglez

you're right i just meant the standard 300$ stock replacement with ngk plugs

Ignition Coil NGK Spark Plug NGK Wire Set RX 8 BWD Euro Free Express Shipping | eBay


a good investment?^ i live in ontario

RIWWP

iTrader: (2)

That's rather high for BWD coils. BWD coils are "fine", as long as you understand you have to replace them about every 20,000 miles (32,000kms?). That listing shows as $302 USD, and in the US, you can pick up that same set of parts at the local auto part's store for about $200 USD. So they are marking it all up by about 50%.

Loki

iTrader: (1)

I don't know much about CMP, but looks like a legit company. While you wait, there are a couple things you could check: that the plug wires are connected correctly, and take pictures of the current spark plugs, we might be able to tell something from that.

And compression test obviously.

Are you experiencing any other symptoms? Hard to start when warm, flashing check-engine light... stuff like that.

triangleztrianglez

i live in canada and no local auto parts store carries them unfortunately.. might have to take the loss and buy them bc im in need of something urgent

triangleztrianglez

it does take about an extra 1.5 seconds to start up when warm and the launch sounds weak compared to starting cold. also one thing that scares me is when i start it warm the rpms flutter from 800 down to about 400 and the cabin lights flicker as if its about to die but then it shoots itself back up to 1000 rpms. its almost as if someones kicking the needle. no check engine light though ever, thank god.

RIWWP

iTrader: (2)

The Check Engine Light should be renamed Check Emissions Light.

Don't rely on it for anything other than emissions control. There are very few RX-8 problems that the CEL will actually tell you about.

LiveWire

iTrader: (1)

If you are shifting above the rpm threshold for the secondary injectors you will be using a lot more fuel.

triangleztrianglez

doesnt it indicate a misfire though?

RIWWP

iTrader: (2)

If the ECU detects a misfire, then a misfire count is stored, and the light will flash.

That doesn't mean that the ECU will detect a misfire, or that a misfire is your problem.

For example, 30,000 miles OEM ignition coils, plugs, and wires were dyno tested and tuned to their max. No CELs, misfire counts, etc... Then brand new OEM ignition was installed and the RX-8 was re-tuned. Net gain 28whp.

No misfires, just a really poor firing event that was wasting fuel and power.

triangleztrianglez

does that mean replacing them will fix my gear 1 and 2 coasting issue where it hiccups and the car jolts every second from 1k-5k rpms?

triangleztrianglez

i'd also like to note that when i bought the car and it was emission tested, the mechanic found that the cat had failed and was replaced with a "new 350$" one. it still didnt pass emission testing and the dealer apparently had to drive it 200kms to "break it in"?

RIWWP

iTrader: (2)

It might.

One of the RX-8's quirks is that virtually all engine issues related to power/efficiency/stability have the same symptoms, with only 1-2 symptoms that vary from item to item. It's why we end up recommending the same set of fixes to every new owner, because until you have the basics covered, there isn't much point in trying to diagnost deeper.

"Basics" means:
- New coils
- New plugs
- New plug wires
- Clean MAF
- Clean ESS
- Reset ESS
- No vacuum leaks
- Reset fuel trims (with 5 minutes of hot idling afterwards to stabilize idle trims)
- No CELs (sometimes they may indicate an issue)
- Not overfull on oil
- Battery connections removed, cleaned, and reseated properly before tightening
- Grounding points clean
- Cat not clogged
- Compression validated as good

95% of the engine/driveability/drivetrain/efficiency/power/etc... related problems we see on the forums ends up being one of the above. Maybe 4% is an intake valve problem, and the remaining 1% is something rare or bizzare.

RIWWP

iTrader: (2)

This very well may be the culprit of the gas mileage. Cat is probably clogging.

An OEM replacement is $1,300 USD. There is one magnaflow part number that has been found and holds up under the rotary's exhaust heat, and it's $100 and has to be welded in. All other aftermarket cats can fail in as little as 2 minutes of hard driving.

Drop your cat and inspect.


Also replace your ignition anyway, since that is the most common reason for cat failure on the OEM cat, which could easily be why the first one failed.

triangleztrianglez

holy f*ck.. is there a way to tell if my cat is fried without having to remove it? (i dont know how to do any of that). and can it be unclogged or do i need to buy a new one?

RIWWP

iTrader: (2)

You need to visually inspect. Use this for reference:
RX-8 Help: Solving Misfires

Scroll down to Bad/Clogged Cat, 3rd from the bottom. There is a series of image links for what the cat should look like inside, and what it will look like if there is something wrong.

Since the cat was just replaced, it should be simple to get the bolts out. Jack up the cat, front has 3 bolts, rear has 2. Plus a rubber exhaust hanger, though you should be able to just unbolt the front and angle it down to look inside with a flashlight.

triangleztrianglez

so i'll have to jack my caR up to access this? would i be able to see if its glowing at night without having to raise my car in any way?

RIWWP

iTrader: (2)

You can see the glow if it's glowing without jacking the car up. However, I don't really recommend diagnosing by a glow to people, since by the time it's glowing, it could easily be damaging other stuff, like the engine. I lost my first engine to a clogged cat.

Loki

iTrader: (1)

You'll be able to see the glow, but you really don't want to test it that way. If it's glowing, you're killing your engine. If you're not comfortable doing this on your own, borrow a friend or bring it to a shop or the dealer. They said the cat still doesn't pass emissions, how can you even sell a car in this condition?

triangleztrianglez

fricken cheap bastard mechanics. is gutting the cat an option? would it save my engine and gas until i could afford to buy a new one?