Low idle problem?

Wat's up people. I have a 97 civic ex that is COMPLETELY stock. Lately, i've been having a problem when the car is at idle. The RPM goes WAAAY low and the car shakes a bit. It goes down to like 200-300 rpm. I recently changed the oil, filter, spark plugs, spark wires, distributor cap, and rotor. The car did this BEFORE all of this work was done and it still does this. Anyone have any ideas? think it's the TPS or something? help please????:(

th easiest place to start is to just reset the ECU and see if that helps it any. from there check that idle air control valve and make sure it still works well. if it is an auto, check your tranny fluid. if it is a stick, take your foot off the brake when it happens and see if you roll forward. if you do, then its to do with your clutch. there are other things to check also, just can think of them right now.

My car does the samething i drive a 95 vx model. When i adjust it to increase rpms it goes up and down @ idle. I check hoses, trottle body for any leaks also checked the idle air control valve nothing works. I brought the car some years ago used and it did it before the mods i,h,e and afterwards. Now im thinking its a weak alternator, belts, or battery.

i dont understand the description about increasing rpms then having them go up and down. the alternator and the battery have nothing to do with this, im pretty sure. the next best guess would be a frozen a/c compressor, or something else sticking with one of the pulleys.

i dont have no ideal why my car does that up and down, but other people had experienced the same problem.

check your fluids, its happend to me before when i had a coolent leak.
the coolent system is a closed system, meaning no air in it. if you have a small leak air gets into the system and air gets hotter then water. the air also likes to fill the cavitys where the sensors are and causes them to report incorectly to the ECU. The ECU tries to compensate and your idol is messed up.

this isnt the only reason it could be doing this but its worth a check.

cool. thanks for all the info guys. i am currently taking auto mechanics at my school and my teacher made me and my partners figure out the coolant flushing system. HE DOESN"T KNOW HOW TO WORK IT!!! but after we figure it out, i'll do a pressure test on my own car to check for leaks.......

Does your check engine light come on? If not you may had bad injectors!