rebuilt engine new coils wires and plugs. checked for vacuum leaks none found. does not matter on rpm will die at idle or 3000 rpm. no cel. help please searches dont turn up exact problem.

 

What problems were you having before the rebuild? Did you do the rebuild yourself, or have someone else do it?

Have you tried clearing the ESS profile? Its like a crankshaft sensor, but for the rotary. Each engine is unique, meaning if your ECU is using your old ESS profile, it wont work very well on your new engine.

https://www.rx8club.com/series-i-tro...memory-169443/

 

Need a bit more info to help

 

i rebuilt it. i got it with broken apex seal. it does smoke a little when running. it will run longer if i unplug maf. but will still just die. all wiring done using manual . put new fuel pump in and bypassed resistor. if i am holding at rpm it will just die like ecu shut off. has to cool down before it will restart.

 

Does it have spark and fuel when it dies?

There are so many things it could be...

Start by rechecking all your electrical connections to ensure it is all wired up correctly. A common error is the injector wiring. It is easy to miss wire the rear part of the injector harness. It will make the car run like crap and idle poorly

 

when its running it runs pretty good has a little vibration at idle and about 2700 rpm. i triple checked injector wiring. still has fuel pressure in line when it dies. i will check spark but when it dies it is the same as turning off key.

 

car is 04 auto. spark is cutting in and out so will replace coils again

 

Check the ESS. ..did you do the reset procedure? ?

 

yes. when i started cranking rear leading coil had no spark for about 2 seconds then the timing light would flash steady after it started then would skip a flash here and there

 

i have the bafx obd2/can interface and torque lite shows 14.7 in of vacuum at idle with 5.7 on maf

 

Don't trust the vacuum reading in torque. It was showing about 5 psi of boost at highway speed on my stock motor. Then i got to thinking and realized I'd never seen a MAP sensor during my rebuild. Turns out there is no sensor and torque is just guessing at the boost/vac values.

Now, after I rebuilt my engine it too would run for a few minutes and just die like someone turned the key. After verifying my fuel pump wasn't overheating etc, finally I had to just drive it. Fired it up cold, dove in circles for about an hour at 3000-4000 rpm, and that's what it finally took. After that it was fine. Holding it at 3k in neutral didn't work but having the car actually in motion did. Just don't stop and don't put it in neutral.

 

thanks i will try that

 

took a while to get a place to drive car but it is still doing same thing after driving for hour and a half. guess seals are not going to seal.

 

Drive it some more 😄

 

Yeah unless torque is reading vacuum from the baro sensor but that number wouldn't make sense.

 

And fwiw there's no actual sensor to read vacuum, it's inferred, badly I might add. Torque shows about 2psi of boost at cruising speed and up to 10 on throttle.

 

The baro sensor is a map sensor so you will get a reading, it's just not installed in the actual engine.

 

Where is it, then? Maf housing or something? That's all I can guess, don't recall seeing anything after the throttle though..

 

Could it be the coolant temp sensor or front O2 sensor?

 

In the stock location the barometric sensor mounts on the air pump bracket. In the RX-8 it is a barometric sensor but the sensor itself is a common MAP sensor used in many cars.