Sy-rx8

Iv put new plugs, leads and coil packs on my rx8 231 , 2004 , when I boot it some times it splutters and try's to die on me this happens mostly when the fuel gauge is on quarter tank!?!?! It feels a bit ruff on idle as Well but not all the time . Any suggestions I'd be very great-full

Junkman 6394226

Did you install everything correctly? Plug all the wires into their proper places?

Sy-rx8

Hi junkman thank you for the reply Yep their all where they should be I didn't find it too hard as it has an L and T on the blocks the leads and coils I did one at a time,

monchie

What is the mileage and do you have any engine mods?

Sy-rx8

Hi monchie , it's only done 50k a d hasn't had any mods yet

wcs

iTrader: (2)

It's not uncommon to have a failing fuel pump in a 04-05

LOL not that's it's scientific but -- if I was giving her all the beans and it sputtered ... after checking ignition I would be looking at fuel delivery.

If you can afford it a compression test is always a nice way to get an indication of your engines health.

Other things free and easy to do (just to eliminate possibilities)
- Clean Maf
- Clean ESS
- Check battery terminals
- Check Air Filter
- Check Maf Screens
- I hate this one but it still applies -- Look for Vacuum leaks

These all could impact the performance of you engine and are free and mostly simple to do.
Cheers

godesshunter

https://www.rx8club.com/new-member-f...thread-246581/

Sy-rx8

Hi WCS , fuel pump and filter on my next to do list . Iv cleaned the maf , air filter , plus new battery today , il pick up a compression tester in the morning , , I had thought it may be a fuelling issue just not sure . Thank you for the advice

wcs

iTrader: (2)

You can't really use a standard compression tester.

Mazda uses a special compression tester that reads the rpm as well providing 3 compression test values ... 1 per rotor face

The best you'll do with a normal compression tester is get a single peak value and no rpm reading.
Alternatively you can remove the check valve from the stem and watch the needle bounce around while someone cranks the motor.
Remember to hold the gas peddle down to prevent restriction to the engine.
Remember to disconnect the ESS, kills the fuel and the spark.

80CUofRAWHP

+1 for the fuel pump. In the future I'd suggest keeping the fuel tank at least half full at all times since the fuel is what keeps the pump cool.

wcs

iTrader: (2)

Good point!
However I think 1/2 tank maybe a bit over kill.
But 1/4 tank I totally agree with.

Sy-rx8

Iv never worked a rotary b4 what's the check valve and where about is it on the engine ? I filled the tank ,I also had the fues on the battery had blow so I swaped for the for abs/dsg fuse, till a new one arrives , its been the best since I got car and no spluttering all the way through the revs

80CUofRAWHP

Well I'm always a lil overkill with this temperamental beast. Better safe that sorry I reckon. Change oil at 2500, change ign components every 15 to 20,000. I run the hell out of it so I just change things sooner than most would to be on the safe side.

Sy-rx8

Finally nailed it , lol check valve bit of a dumb ars response from my self , popped it in to a Mazda dealer for a compression test and got 6.2 / 6.7 no rpm or any more read outs from them , I found this a bit odd as once I got rid of the rx8 gremlins it flys 136mph in 5th with 6th to go ?!?!?!? It certainly dose not feel like its compression is low ... As for the fuel I keep it well over 1/4 it's fine and runs so much better

Loki

iTrader: (1)

Compression on these engines is a funny thing, you don't really know it's low in some cases.
But they should give you 6 numbers (3 per rotor) at a given RPM. If they don't give you that, don't pay them

Sy-rx8

So the reading I got won't mean anything . Without the other readings and rpm . When I first got it it ran like crap always breaking down now it flys better than I expected I'm getting 25 mpg at low revs , flat out its crazy

RIWWP

iTrader: (2)

6.2/6.7 at 200rpm is a good engine
6.2/6.7 at 250rpm is just above failing
6.2/6.7 at 300rpm is a miracle it's still running at all

RPM and 6 individual numbers is what you need. Generalizing it doesn't work. You not only need the lowest value of the 6 rotor faces, you need the difference between any 2 faces on the same rotor, since all numbers can be passing but if there is too great of a difference, the engine is considered failing.

This is explained in the new owner's thread, among other things.