I'm new to the forum and don't know much about cars, but here's my problem and hope someone can help. I hope I can describe it well enough to understand.

I have an 84 RX7 12A, 87,000 miles. My problem is when I accelerate normally changing gears and such everything is fine. But when I accelerate to the floor, letting off gas to change gears, instead of the RPM's decreasing when gas is let off, it does the opposite and revs up to 5 to 6000 RPM's, but eventually goes back down.

This is what I can tell/see. When I depress the gas pedal with engine off, there are two things I notice that move...passenger side between the wall of the whole engine compartment and the carburetor...a cable that pulls a "spring" and the other is what I call a "plunger" like thing. The second cable pulls the bottom of this "plunger" thing open and the inside plunger thing drops down. I don't know what these are called, but I noticed the plunger thing sticking a little and not moving smoothly. I am assuming that when flooring the gas, the plunger thing was sticking open even after releasing the gas pedal, continuing to feed fuel and that's why my RPM's continue to rise even after I let off the gas. I sprayed the plunger thing with carb cleaner and worked it around trying to clean up the gunk, but the problem still persists.

I've just replaced spark plugs, wires, distributor cap and rotor. Can anyone shed some light on what my problem might be?

 

the "plunger" sounds like your dashpot, its supposed to make the throttle close slowly if you let off the gas to prevent backfiring. Try removing it to see if your problem goes away. If you need one, Im sure someone on here will give you one.

 

Thanks for the info. So am I understanding you correctly...remove it completely? Is this not needed?

Debbe