New to the beautiful RX-7, please help.
 

Hello everyone,

I just recently bought a '91 FC3S (S5, NA), and besides the fact that I love it, I am having some issues with it as well, and would love you guys to help me out on how to fix them, or at least telling me what I should check/do.

I'll list the issues that I am facing at the moment -

1. Idle is erratic, between 500 and 750 rpm, going up and down, the car even goes to about 1100rpm at certain moment while idleing.

2. A lot of juddering/bucking, mostly on deceleration, but also present on acceleration.

3. I have the stock audio system, with the casette player and equalizer -- it works alright, but seems like the speakers go off every once in a while, for no apparent reason. The audio systems stays on, but the speakers don't emit any sound. Then, for no apparent reason, they go on again.


Regarding the first 2 issues, I have read about TPS adjustment procedures, but I was not able to find any clear guide on how to calibrate the TPS on S5 FC's.

Also, having the A/C on and stuff doesn't modify any of the previously mentioned issues.

Any help or feedback would be greatly appreciated.


Regards,
-Dan

welcome, the idle on S5 NA's aren't really ever perfect, adjusting the TPS would definitely help it, if it gets worse I'd try another BAC (bypass air control valve) and adjust it with the screw on the TB. Number 2 definitely sounds like the TPS either being bad or out of spec. Check your wiring to the speakers to see if anything is exposed and possibly making contact with metal anywhere on the car.

Thank you very much for the reply.

I would like to know, where can I find a good and detailed TPS calibration tutorial for my model?

Welcome to the forum. In my sig line is a link to the online FSMs. Download whatever you need. Before you try a different BAC, take off the one you have and clean it with some brake cleaner. I don't spend much time in the 2nd gen section of the forum, but there may be a 'How To' in the archives for adjusting the dual tps's.

The TPS sits on the front of the throttle body and connects to the Electronic Control Unit (ecu) by a 5 connector electrical fitting. With the engine fully warmed up and off, disconnect this fitting and check the resistance using the top right and bottom right pins of the fitting (TPS side, not the ECU side). Resistance should measure 1000 Ohms. If it doesn't, turn the TPS adjustment screw until it does. Then go back and adjust the idle to 750.