well heres the story and im gonna try and make it as short as possible. i have a 1991 civic hatchback dx with a gsr swap.. i have this idle problem thats driving me nuts since i cant find out whats causing it at a cold start the car fires up just fine and sounds powerful, but as soon as i drive it for maybe 10 min it starts to idle really bad (reaching 170-190 degrees) if i turn it off at that temperature and try to crank it again before it cools down it starts but starts really soft/smooth. but not smooth as in good, smooth as in bearly starting then it has a horrible idle and sometimes just dies. if i pump the brake pedal the idle will go away temporarily but as soon as i drive again and pop it out of gear when coming to a stop sign or something the idle problem comes back. it only idles like that when it warms up.. every cold start is great! heres what ive checked and changed so far. i checked for a vacumn leak with break cleaner on my hoses and i found nothing, i changed the IACV with another one (used) but still didnt seem to change anything, i changed the ignition module(new) thinking that could be it since those dont function the same when they arent good and get hot, i changed the fuel filter like 3 months ago, i checked my fuel pressure regulator for leaks and found none. my car doesnt have the EACV i think thats what its called, i could really spare some help from you guys since ive done what i think could be wrong.. im not a car expert so i couldve changed parts that dont even matter lol well let me know if you could think of something that i havent listed! thanks guys!!!

 

sorry guys i tried to double space but somehow it still came up like that

 

Any CEL light and ECU codes?

 

no check engine light at all only when fuel pump primes then it goes off

 

Clean everything i mean everything. check your lines make sure theirs not a leak adj. your idle air screw see if it helps the basics to the idle problem every honda has.

 

when u say clean what parts do you mean? lol and i kinda checked the screw but do you think that could be it since the idle is only when the vehicle reaches running temperature

 

Are you having an idle problem or an engine temp problem? Or both?

 

its an idle problem after the vehilce reaches running temperature. the temperature is perfectly fine

 

It can't be a vacuum leak as this would make it idle too high. Sounds like a mechanical linkage issue at the throttle body. I would try either adjusting the idle air screw or bending the tab at the throttle stop. The throttle stop is the part that is spring loaded and you can rotate by hand to rev the engine from the throttle body.

 

i have the same setup as yourself and had the same issues one thing to try is to pull out the ecu fuse under the hood for 15 min...after that put it back in and start it but dont touch the throttle....allow the car to idle till the fans go on and off twice then take it for a ride and see...

also what ecu r u running i see your name has obd0 are you running a chipped pr3 or pw0 if your using a tunning solution like BRE you could ajdust the idle in there....that help me ALOT...

 

@ zeppelin ill give that a shot man! and the sprivg loaded thing isnt that the eacv? what your saying does it only do it when the vehicle reaches running temp? since mine only idles like that when it reaches running temp not on a cold start

 

@ frazzo203 well i have my fan hooked up to the ign switch for it to cut on as soon as i cut the car on since i couldnt get it to work where its actually suppose to go lol and its converted to obd 1 running i think on a p72 tuned to the motor. one thing i noticed is that my IACV is plugged where the vacumn hose goes idk if thats normal or not..

 

BUMPP!! i really need some help guys

 

i did a ohm reading on the iacv plug and i put the tips from the ohm meter one way and i get like 3.07 i think they i put the tips on the opposite ends and get 6.88 is that normal?!? on the ohm meter its on the 20k