Mesh Graves

Hello I have a Mazda rx8 2004 and it runs great until I come to a stop or red lights, it shuts off on me and the idle drops under 1! Ive had a oil change transmission fluid flush tune up coils changed spark plugs compression test from auto zone what else could possibly be the reason for it to keep cutting off!! #hhhheeellllpppppp!!!!!

Williard

iTrader: (18)

Autozone doesn't do compression test's so you didn't have one done.


So, more than likely it's compression related. You should get an ACTUAL compression test done.

Any CEL?


Travis

9krpmrx8

iTrader: (46)

Look at the troubleshooting guide by symptoms here:

http://foxed.ca/rx7manual/2003mazdar..._S01_0016.html

Khurram

Also, get your car tested for vacuum leak.

In the interim, go over all the intake hoses, if any of them are compromised that will cause your messed up idle and vehicle to shut down if it's not under load.

While you are at it, pop the air filter out and inspect it, clean it or replace it :-)

and Get that compression test done at Mazda or a rotary mechanic.

cheers,

iTs Ghastly

Just recently posted this on another thread, here is what you need to know about compression tests; 1. Your typical mechanic is not capable of preforming this. It isn't a complicated process, but your typical compression tester is not equipped to give us the information that we require for an appropriate compression test.

When you get your compression test it should have 3 numbers per rotor, as well as the rpm it was tested at. If your compression test results look anything like
Rotor 1: 80psi
Rotor2: 86psi

or
Rotor 1: healthy
Rotor 2: healthy

or anything with just one number per rotor or no numbers at all, you did not get anything meaningful from your test.
ideally you should get something that looks like

Rotor 1: 110psi, 108psi, 110psi
Rotor 2: 110psi, 110psi, 108psi
RPM: 250
then adjusted to your altitude at area of testing.

measurements can be in other units but you want 3 numbers per rotor and your RPM with your results

with your results after normalization you can verify good compression via this chart
http://www.rx8help.com/img/compression_chart.png

The typical compression tester for piston engines are only capable of giving us the peak psi and no RPM, which essentially is useless, which you can easily see when looking at the chart used to diagnose our engines.

For example, my engine recently had an apex seal **** the bed. My numbers were 301rpm, 68psi , 32psi , 32psi . With your typical comp tester all you would have seen is 68psi , with no RPM , unadjusted to altitude, etc.

In short, get an appointment with your local rotary specialist, or Mazda dealership, and when getting your results, make sure your results contain all pertinent information

Nisaja

The car normally idles under 1k. It's around 850 RPM. When it shuts off, can you start it back up? Does it drag while starting? If you keep the rpm high, does it stay on without shutting off? Do you have the AC on? Try turning the AC off and see if it still stops. Sometimes when the AC compressor gets stuck, it can make the engine shut off at idle.

Check the basics before thinking about compression.