I've had my Rx for about five years now. the engine had I think 10,000 miles on it when I got it. But for some reason I've always had a miss durring idle. It's short, but as she's idleing you tend to hear this split second break. Ive changed the plugs, coils, wires and reset the tps. nothing has stopped this hesitation. does anybody know what this could be.

 

might be your BAC, I know mines bad for a fact (idle sucks) and mine misses at idle too.

 

Yeah pre-Renesis rotaries do that, something to do with the exhaust entering the intake on the next rotation.

 

So then this may basicly be a normal thing that indicates no problem?

 

Funny seeing how the exhaust would also enter the intake on the rene if this were true. On all motors not all exhaust gasses are ejected from the motor on its exhaust stroke. Besides the small amount of exhaust gasses from that would not cause a miss, have you ever heard of an EGR valve, and do you know what it does with the exhaust??

But back to the question

Check all your grounds and clean them this is a normal problem. Do not forget the one under the UIM, arroncakes website(plus the FAQ) has a good write up.

 

This is a thread hijack! Would this problem also present itself as a miss on deceleration; basically the situation where the engine is being driven by the wheels?

 

i had a bad misfire on idle too, but once my cars warmed up the miss isnt as noticable or the frequency that it occures decreases. I havent found the cause of it yet unfortunatly. I hate the electricals of my s4 i have the urge to rewire everything in that damn car.

 

Mine does it too, and my engine runs like a top!! Looking at videos of other RX-7's idling, most of them all did the exact same thing. I wouldnt let it get to ya.