MisterWise

Hi
I am still learning about civics...right now i have an idle problem
When i am neutral, it will revv up to 2000rpm and down and up...
it only did that when i drove for while...but now when i turn my car on it starts to do that.
Friend of mine told me change out the o2 sensor.
HELP ME OUT PLEASE

wrenchez81

ok...now.. what is actually happening is your computer is cutting fuel pulse in an attempt to lower the idle because its too high... thats why its "fluctuates" the computer drops fuel pulse and the engine tries to return to its high idle..... bottom point is your idle is too high!!! check for vacuum leaks,,, idle bypass screw(usually works) and ur ignition timing.......DEJA VU!!!!!!! also check the throttle cable adjustment.. ADJUST IT TO SPEC!!! THIS IS CRITICAL!! had the same prob on my del sol.......went crazy finding it but came to the conclusion that it was just ever so slightly tought causing the issue....... good luck ami go!!!

honda.lioness

First thing I would do is top off and thoroughly purge the cooling system of air, per the 95-97 Civic manual linked at http://ww1.honda.co.uk/car/owner/workshop.html . Certain engine sensors must be fully immersed in coolant to work properly. If they are not, they send the wrong signal to the computer, and idle problems are common.

Note that, during the purge and per the manual, you have to wait for the cooling fan to come on twice. This may take 40 minutes of more of the car idling, so have a magazine...

OTOH, if this car is one that has been modified, the possibilities for what is causing the problem are many.