Hi, I recently bought a Re-Amemiya ecu wich is set up to work with open air filters and 3" exhaust. I bought it from a jdm rx-7 and I was not sure if it would work on my US-spec rx-7, but it works perfect EXCEPT from one thing; When the engine is warm the idle rapidly goes between 1500-3000rpm

This only happens when the engine is warm and it happens after 15-20 sec of perfect idle (around 8-900rpm)...

The mods I have done on the car is 3" exhaust all the way from the turbo's and out, I still have the original air filter box, could that possibly cause this problem?

 

Nobody know's what it could be???

 

Hi Alec! I also bought a Knightsports ECU and have similar problem. My idle is all the time bouncing between 200 and 500 revs (when warm).

Try to adjust the TPS and see what happens.

The problem with these ecus is that whenever you need to re-program it, you wouldn't be able unless you have it setup by (in your case ) Re-Amemiya.

 

Did it work for you to adjust the TPS?

I have tried to unplug the TPS but with no help...

The strange thing is though, that sometimes the car acts 100% normal on idle and all sudden it sometimes bounces between 1500-3000rpm

 

No nothing happened. At first i thought that all is ok but after a few seconds it was bouncing again

I contacted Knightsports and they told me that it could be a problem of knocking caused by bad fuel. In japan they use 100octane and here we use 95Ron. So that might be a problem. They also suggested that it could be a problem of air-fuel ratio. The best choice to do is to handle them the ecu a re-program it to my spec. However, its still expensive to do so. I am still trying to get my car up to the spec of the ecu. If i'll do not succeed then i would have no other choice.