Hey everyone,
I’m the definition of new to the rx7 world. I just purchased a 1986 RX7FC. I absolutely love the car. It’s a southern car, super clean but has one issue. When the car is cold, it will not hold an idle. It will die almost instantly. I have to hold the gas for 5-10 seconds and then the car will idle fine on its own. It has about 90k on the dash. I know the car has been sitting for a little bit. The fuel filter is relatively new. The person I bought it from bought it 5 years ago and never registered it. So I can imagine it sat for a long while. Does anyone have any recommendations on what I should start digging into? Any advice will help.

 

Is the car entirely stock? Has anything been removed, such as the emissions or things been simplified?

Your FC would have come stock with a high-idle startup, which is a mechanically driven system to hold idle to 3k rpm for a short bit, and then idle down slowly to allow the idle control system to take over. Over time, those either got pitched, or they stop functioning.

 

The car is stock. I know it was dyno’ed. Not sure if the car was tuned on the dyno. The previous owner bought it and had zero knowledge about the car. He “bought it from a friend.” On the left side of the motor there is a block plate. It’s behind the “air pump” which is not connected to anything. I was told the stock height adjustment was removed because of the coil overs. But other than that, I don’t see anything else that was tampered with. After I hold the RPMS for a few seconds the car will idle itself. It definitely does not start idling at 3000 though. Attached is a picture of the block plate.

 

From that picture, it looks like your 5th and 6th ports are wired open. So yes this car's been messed with along side that block off plate.

 

What exactly could be a result from having those ports wired open?

 

The aux ports act a little bit like valves that open at specific RPM/load conditions to allow more air/fuel into the engine. They are normally closed at low RPM/load to increase air velocity into the engine, improving torque and driveability down low. When you need extra power in the upper end, they open.
Having them wired open means you lose that low end grunt AND the smoothness of idling can be a little more challenging. I don't suspect that is the only reason for your idle quality issue, but it isn't helping.
Does your car have an aftermarket exhaust on it?

 

Hey, if it helps it’s a start. I will try to do some research and figure out how to close them so they’re not constantly open. It does have an exhaust. It seems to be custom. I’d have to look when I get home but it’s definitely some custom piping.