1995 honda civic with 1.5 l car is surging at idle if you press the gas pedal car evens out and runs nicely.

things i have replaced on car
1 iac valve (twice)
2 intake gasket
3 throttle body
4 tps sensor
5 map sensor
6 2 coolant sensors
7 timing belt water pump and thermostat (friend recommended to replace since it was orignal with 140,000 miles on it)
8 rack and pinion (leaking)
9 spark plugs and wires cap and rotor
10 exhaust system from cat back (rusted and had holes in pipe)

i have used several cans of brake clean to hose down motor for poss vacuum leak and none to be found. if anybody has anything else i could check or replace please let me know

temp blocked off air hole to iac valve car idles at around 500 rpm and no surging. took on interstate and ran good. until i let of gas at exit ramp. started surging but not as hard. drove around for roughly a hour on interstate driving and when got home i popped the hood and happen to check hoses from rad. the lower rad hose was not hot. car was at running temp. it that normal

 

Check your Ignition timing with a light gun!
Sounds like its a IACV issue though. Maybe the wrong plug is on the IACV but I doubt it.

 

out of curiosity i have read on here that many people have blocked off or eliminated the iac. would it hurt the motor or any of the systems to do that?

 

YES do not remove the IACV it plays a big role on post start up as well as fuel compensation, the ECU will look for the sensor to run the engine correctly.

What ECU do you have?

 

not for sure. where do i check to find out