Hi everyone,

My name is is Sam, and I finally made an account on H-T and hope to contribute in anyway I can. I feel bad because my first post is pleading for help on my 1992 Civic CX Hatchback that I have owned since new.

The car has always had it's preventative maintenance done ahead of time since I purchased it brand-new in 1992.

The car is 100% stock, 5 speed, and has 160k original miles. It runs great. no over heating, or even loss of gas mileage...

However, recently I started to get a "surging" idle that occurs when the car is warmed up. It fluctuates from 1000 to 1300 rpm's. I have replaced the IACV, all the gaskets on the Intake manifold, and have bled the coolant system at least three times, and it has NO vacuum leaks or check engine light. I have used the search engine here and Google and for the life of me cannot find out what is causing this?

As mentioned, the car has the 100% stock original CX D15B8 with 160k miles. Is there any other advice that someone here can give me as a point of reference? There is no FITV on the CX engines, and I have (what it seems like) ran out of options as to what can be causing this.

ANY help is much appreciated, since my car is due for a smog soon and I need to get this issue rectified before going in for a smog check.

Thanks again,

Sam

 

When the idle is hunting, can you prevent it by using your finger to cover the hole leading to the IACV inside the throttle body?

Did you bleed like this:
https://honda-tech.com/honda-civic-d.../#post38664177

Does the CEL work?

ECU inputs from the TPS and ECT sensor also affect the idle speed.