1993 Honda Civic w/stock engine.

My car is idling around 550 RPM, and the result is that it idles rough. I wanted to raise my idle to around 850-900.

After turning the idle screw almost all the way out, the idle remained the same. I then thought that the o-ring around the idle screw was worn out. I replaced the screw with a brand new one from Honda.

Unfortunately the screw did not solve my problem, I am still stuck at 550 RPM's. I am able to lower my RPM's, but I can still twist the screw almost all the way out w/o any change in idle.

What else could be the problem? I have new plugs, cap and rotor installed. Keep in mind that I am looking to install a new engine in December.

Thanks


[Modified by 93SSPHatch, 6:13 PM 7/31/2002]

 

Maybe the air bleed passage is partially pluged. Take out the adjustment screw and hose out the passage with t/b cleaner.

 

did you try messing with the distributor?
also make sure that you have all the vaccuum lines in the right place.

 

I have not messed with any of the vacumn lines, and the distributor was moved to adjust my timing.

Would messing with my distributor help to solve this problem, or would it just send my timing completely out of whack?

I'm not really sure which lines are vacumn lines? On my old 84 Corolla, it was very easy to tell which were the vacumn lines. . .I don't know very much about Honda engines (I am slowly learning).

Would you care to describe/show me which lines are the vacumn lines, or where they connect to.

What else could it be?. . .the IACV?

Thanks

 

there was a vaccuum coming out of the throttle body next to the idle screw which i recalled caused the idle to be low and rough. vaccuum lines are all over the intake manifold....i cant really draw a picture you would have to mess with them to see which hoses are which. have you used the timing gun for the distributer?

 

I may be incorrect but I believe there is a sensor you unplug on the back of the intake manifold to get the base ide. then you can adjust it from there. I believe this is what its says to do in the Helm but i dont have it handy. I forget what sensor it is but we unplugged it and set the base idle with the screw, plugged it back in and went from there. Good luck.

 

ill phil: I think you might be referng to the IAC valve connector. I forgot to unplug this when I attempted to change the idle. Maybe if I unplug this first, then adjust the idle, things might work out.

As for the distributor, yes, my friend at a performance shop used a digital timing light.

 

Yeah thats what I'm referring to, couldnt think of it off the top of the head. When you unplug that it will give you your base idle, which should be somewhere around the 550 you have right now.

 

If that doesn't do anything, try cleaning the throttle body. Frequently, gunk in the TB will throw off the the idle.

 

Just make sure you re-set the ECU, after unplugging the IAC, and adjusting the idle...

 

Does it really make that big of a difference? I've yet to give it another attempt. When I get back from work today, I am going to mess with it again!

Keep the suggestions coming. When I looked at the throttle body, it did look very dirty. Where/How do I go about cleaning it? I would imagine that I remove the TB, then maybe soak it in TB cleaner, I am really not sure.

Thanks

 

Buy a spray can of carburator/throttle body cleaner and follow the directions on the can. With most of them, you just spray it into the TB while the car's running.

Check to make sure the can says the stuff is safe for O2 sensors -- I'm pretty sure they ALL are these days, but you never know.

 

Thanks for the great suggestions, unfortunately I got off work really late, and I have not attempted to mess with the idle today. I will have to try tomorrow (if the girlfriend doesn't flip ****).

Thanks