I remember seeing a thread out there about this exact problem but search turned up nothing. The car is stock except downpipe and airbox mod. The problem started after replacing the alternator.

When I start the car it goes straight to 1200 rpm. After letting the car warm up I take her out for a spin. She runs perfectly. When approaching a stop, I put it in neutral with the car still rolling. Whether I'm going 60 mph or 5 mph the engine runs at 1500 rpm until I COMPLETELY stop then it drops to 1-1.2K rpm.

When I pop the hood with the car running i can turn the throttle back and the car will drop to the magic 750-800 rpm. It stays there until I tap the gas and it will jump back to the 1.2K idle.

I know this has been answered before but again I did search... THanks for the help.

 

[QUOTE=Black1993rx7;7042132]I remember seeing a thread out there about this exact problem but search turned up nothing. The car is stock except downpipe and airbox mod. The problem started after replacing the alternator.

When I start the car it goes straight to 1200 rpm. After letting the car warm up I take her out for a spin. She runs perfectly. When approaching a stop, I put it in neutral with the car still rolling. Whether I'm going 60 mph or 5 mph the engine runs at 1500 rpm until I COMPLETELY stop then it drops to 1-1.2K rpm.

When I pop the hood with the car running i can turn the throttle back and the car will drop to the magic 750-800 rpm. It stays there until I tap the gas and it will jump back to the 1.2K idle.

I know this has been answered before but again I did search... THanks for the help.[/Q

I have the same issue, what did you find?

 

sounds like your throttle cable it sticking in some fashion....do you have cruise control on your FD?

when the car initially starts it will kick up the RPM for what mazda likes to call "accelerated warm-up", most people disable this system because it can be worse for the motor on cold days