own a 2004 RX-8, changed plugs,coils, and cat, car will heat up and shut down for about 30 - 1hr start right up? can gas cause this? after replacing the cat, been running good, but rough yesterday after a fill up?
To see if the trouble is fuel related simply spray a small amount of starter fluid into the intake when the trouble happens. If the engine fires then you know the trouble is with the fuel delivery somehow. If it doesn’t fire up then the trouble is most likely with the ignition system.
Very unlikely it is the gas, do you have any check engine light? you should. If not get the codes read and see what they say, free at many auto parts stores.
After replacing the cat, thought that was causing my problem, will continue to investigate
thanks
Google this; 01-008/05 mazda bulletin pdf
Do you have any of the listed symptoms? If you do, it might be worth paying to have the PCM flashed. I’ll assume the dealer would charge more than 0.3hrs, as you’re out of warranty.
Early Mazda RX-8’s had a whole slew of problems that lead to poor starting.
What you described, and correct me if I’m wrong, is this:
When the car is ice cold (first start of the day), it cranks up perfectly fine.
But after you drive the car for a while, if you do a short stop (say to refill the car with gas), you then have a hard time restarting the car.
If this is the correct problem, there are several causes for this.
Poor primary ignition system.
Ignition coils, spark plugs, spark plug wires.
Luckily, you have replaced all of these already.
Clogged catalytic convertor.
You’ve already covered this one, too.
Weak starter.
The early '05 and '5 RX-8’s were shipped from the factory with a weak starter.
As time rolls on ,they are no longer capable of cranking the engine over fast enough to build up enough compression in order to fire up the rotary engine.
A replacement starter spins faster, increasing the compression just enough to make ignition happen.
Weak battery.
A weak battery spins the starter slower, and this leads to similar problems as mentioned above.
Faulty fuel pump.
Again, early '04 and '05 fuel pumps were not the longest lived items on the car.
They tended to cause more issues that wound up being blamed on other components, until someone pulls out a fuel system pressure gauge, and tests the car.
Low compression.
Weak compression leads to not only low power, but hard starting.
All RX-8 engines from '04 through '08 have the tendency to lose compression over their lifespan. Some engines needed to be replaced early in the car’s life due to faulty ignition and catalytic convertor parts that lead to rotor housing damage, or badly carboned apex and side seals that decreased compression to the point that the car becomes unreliable.
Only solution for low compression caused by wear is a full rebuild.
Carbon caused compression loss can be cleaned out with heavy doses of carbon cleaner, to the point that there is a special procedure to perform carbon cleaning on rotary engines.
And no, I didn’t stay at a Holiday Inn last night.
I own a 2011 Mazda RX-8.
BC.
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negative ghost rider, follow this for your solution. Alittle late granted, but like my step brother you used to,if at first you dont succeed, keep suckin. Hopefully this helps someone who stumbles across it,
1st..check the ground that is under your intake plenum,you have 3 ground points, the one I referenced was one of my issues.
2nd..look at your intake air temp sensor, it is combined with your maf sensor on your model.
3rd..look at your fuel pressure, pay close attention to your gas gauge. Our models for some reason dont like to run with anything under 1/4 tank. Irregardless pay attention to your fuel at the rail.
4th..This was my gremlin..look at your fuel injector seals on both the rail and the intake. My spitters were spittin where they shouldnt have been, leaving cute little pools of gasoline in nooks and crannies.
5th..look at your upstream 02 sensor, downstream not so much.
6th. This is one of the things I ruled out first, Look under your air pump, grab that thing that looks like a mini amplifier. That is a fuel pump resistor. My reasoning was that because my bucket would shut off when it got so warm, because resistor would get hot and trip. To verify this I crossed the 2 wire at resistor with no changes. Something to think about.
lastly coolant temp sensor.
In conclusion, I pinky promise I had the exact same problem, now she purrs like a kitten and doesnt even think about stalling at stoplights. Cheers
12 years is more than a little late and the person has been gone and may not even have the vehicle anymore.
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