hi. bought my rx8 a few months ago and this problem has been bugging me from day 1. its like the first part of the throttle does nothing and when you press it slightly more you get a response. this makes smooth driving very difficult. its driving me mad. i was thinking maybe the throttle needs changing but thought someone on here may have come across this before and may be able to help.

thanks

 

ideas?

 

the RX8 has a throttle-by-wire system, not a hydraulic system, first of all. So it could be an electronics problem.

 

throttle position sensor.
Coils and plugs.
or low compression in one of the rotors.

 

i know it is a throttle by wire system. that's why i was considering changing the throttle pedal. it is as if the very top part of the pedal is dead. the engine otherwise runs perfectly and always starts fine. what are typically normal readings from tps etc. when i plug in? should the throttle go from 0 to 100%? i know there are a few different throttle read outs though.

cheers for help

 

If the throttle pedal was giving strange readings your car would go into limp mode.....there are redundant backups in the system that if they do not correlate the ECU shuts things down

The throttle reaction is designed to make driving smoother...in low gears and RPM...small variations of the pedal make less difference

The mapping of the throttle can be changed to improve with an AccessPort...talk to MM about that

 

ask MM about his reverse throttle tune. Pushed to the firewall is 0%, all the way up is 100%. Would make for a much more interesting daily drive.

 

i doubt the car was mapped like that. it makes smooth driving near impossible. you have to judge when the power will start to be delivered rather than it starting at the top of the pedal. it is really hard to explain. when going from overrun back lightly on the throttle the very first bit does nothing then as you press it ever so slightly more the car jerks as it comes back onto the power. also when you rev the car gently in neutral pressing the pedal very lightly i am unable to raise the revs by a couple of hundred rpm. the first response i get from the engine is when it jumps upto about 1300 rpm. it really feel like an electrical problem with either the pedal or tps to me. i recently drove an mx5 with the tps wrongly adjusted and it felt much the same. how do i determine which is the culprit though?

 

If you can borrow a TB...I would start there...it is an easy swap and that likely would be the problem. The pedal sysstem has an inverse relationship between the sensors..and if it sees something strange it limp modes...............

 

So the dead spot is at full throttle?

 

Sounds like MAF, not throttle.

 

How many miles on plugs,coils,wires and what mods do you have?

 

I have noticed this in mine as well. I dont think there is any problem though, i believe it is just how the car is made. i dont know maybe im wrong...