sometimes when i stop for a red light or stop sign, my car goes down to about 300 rpms. it will shake the whole car and will not stop. sometimes it will die because it idles so low. i dont have any idea whats wrong with it. ive heard stuff like clogged fuel injectors, dirty fuel filter, idle air controller, o2 sensor, out of timing, valves not adjusted, or lost compression. i dont know which of these it would be. the only modification it has is an aem short ram intake system. please help me out!!!! thanks.

 

Any cels?

 

check your vacuum lines around the intake and intake manifold.

 

idle air control valve?

 

I got the same issue...new fuel filter, timing is right, plugs are new, air filter new, mafs is clean, NO CELS.
I had the a/c compressor locking up, so I had that replaced only to find out the expansion valve was clogged. So, it is not the A/C system...new timing belt. I have no idea why it does it.
Battery is fine, alternator is fine...
Anyone had this issue before??? I have a D16y7 on an ek hatch, 72k miles.

 

no no cels or anything. its a d15b8 by the way. i checked advance auto parts about a new iac....its like 198 or 298 dollars i think. i could almost swap the motor for that much!! lol

 

get a manual and a multimeter and start testing things one by one. iacv, map, tps, etc etc. dont just start spending cash on replacement parts that might not be broken in the first place. ive read about this same issue many times on several forums... theres a few things that can do it so it seems to be very hard to diagnose. im about to invest in a multimeter myself here soon.

 

Most likely its you IACV! Take it off clean it and fix it.I think there is a write up at FAQs might be wrong search for it IACV

 

Just measure the resistance across the terminals on the IACV and see what you get. It will tell you if it is bad...if so, cleaning will not solve the issue.