RPMs drop when engine is warm - Mazda Ba 323 1997
 

Hi!

I've got a Mazda Ba 323 from 1997 with quite an annoying problem.

Whenever you start the engine when it's cold or medium warm, it runs fine in the beginning. The problems arise when the engine is warm.

1. When the engine is warm, it's starts weird. It starts up fine but the RPMs instantly sink down towards 100 RPM's. After about 2 seconds, they go back up to normal 700-800 RPM's.

2. When pushing the clutch with a gear enganged, the RPMs drop down towards 100 again, stabilizing 2 seconds later.

3. When turning the wheel left or right, the RPM's go up and down.

Do you guys have any clue whats going on here? Any help is appreciated. It's driveable, but it's extremely annoying.

Here are two video clips of how it behaves:

http://www.youtube.com/watch?v=aYkuREz5LxE - From the inside: Engine start, acceleration (normal) and turning of the wheel.

http://www.youtube.com/watch?v=vtvoGjyQeFU - From the outside: When turning the wheel slightly left or right. Sure, in every car the RPM's drop, but not by this much.

Bump.

My IMHO’s are as follows:

Item 1 – could be due false air, check intake manifold (all the gaskets etc.) for air leaks

Item 2 – could be due to faulty clutch switch and / or neutral switch in the transaxle.

Item 3 – if RPM’s go up & down quickly and only one time per wheel turn it is OK