my car is idleing pretty low at around 200rpm, the whole car starts to shake and it sounds as if the car is trying to shut off. when in park i push on the gas a little until its around 600rpm, at that rpm the car is real quite and smooth. so my question is do most cars have a idle speed control? if not would'nt it be smart to block the throttle body so that it cant close as much as it usally does so that it can achieve a constant speed of 600rpm idle?

 

There is a screw for adjusting your idle. It will be on the outside of the TB. You will need to loosen the hex nut and then you can adjust the set screw with an allen wrench.

 

Actually I bet your IAC valve is stuck or has otherwise taken a dump.
But since you have a 2007 Ferrari I'm not sure if it has an IAC

 

why dont you start by posting year and model ??

 

he he its a...... 1996 mazda 626 LX, but before you guys jump me for posting a mazda on a honda forum i know i know its a honda forum not a mazda forum, but i just wanted to know if most cars have a idle speed control. plus i have a 1990 honda accord EX so i still pass... right?

 

no. i feel so violated....

 

G.K I think you need a hug.

 

yes, it should have some method of idle speed control. if this just happened out of nowhere there is a reason and you should troubleshoot further to find it. don't "block" your throttle body to adjust your idle.

 

im not sure it just happened its a car im looking to buy they had to replace the gas filter because it was too dirty to run the engine properly, since its been changed it runs alot smoother, i get the feeling that this car was owned in an area that may have had alot of dusty dirt roads because alot of things seem to be clogged or dirty. could this be a small problem like dirty PCV valves or fuel injectetors, dirty oil or is it most likely a costly problem? like a cracked piston?

 

it could be as simple as a clogged IAC (whatever the Mazda equivalent is) or it could be down on compression. If you're considering buying it I strongly recommend doing a compression test on the motor first to make sure the bottom end is OK.