95 Civic DX Idle Problems

[greytek2002]

About a month ago now I had my head gasket changed. Ever since then the idle seems to be very low and almost at the stall point. It feels like the car is choking. Even when I'm going down the road at cruising speed and take my foot off the gas the car sputters a bit. I also noticed that my engine sounds a lot louder now inside the car. I'm not sure if after a head gasket change the car takes a bit to get worked back in or something? If anybody can help that would be great!
Thanks for your time.

Greytek

[superbluecivicsi]

do you know how to do a compression and vacuum test. it will pinpoint the problem. search the site because ive written about it a few times. if not, take it to your local mechanic. they will know what to do.

[typerx7]

try adjusting the idle first.....theres a screw on the throttle body right behind a black rubber tube...( to the left of the map sensor on top of the throttle body) ....tahts wat u adjust...install a tach..run the car til the engine heats up to Normal operating temp. shut it off. unplug the idle positioning sensor i believe its called....(its the cylindrical looking thing on the back og the intake manifold., the sensor will be the vertical one) start the car with the gas pedal slightly depressed. level the cars rpms at 1000 and slowly let it drop into its idle...once it drops adjust the screw looser for higher idle or tighter for lower idle. idle should be set for manual, 570-720 rpms....autpo im not sure but i know its lower. after adjusting it to the correct rpms...turn off the car, reconnect the sensor and reset the ecu by pulling either the ecu fuse or 7.5 amp backup fuse for 15 secs....replace and there u go..

[polacek]

I am not sure if I would touch the idle adjustment screw as the issue happens while the car is running. I'd adjust the screw as a last resort. I think superbluecivicsi suggestion is the way to start. IMO, raising the idle doesn't rectify the problem, only covers it up for the time being.

[typerx7]

the compression in the cylinders and vaccum in the head wont affect idle at all....check your pcv valve, hose and put a tach on to see the idle....then go from there..oh and clean out your iacv valve too, thsoe things get dirty and cause iradic behavoir with your idle

[superbluecivicsi]

Originally Posted by typerx7

the compression in the cylinders and vaccum in the head wont affect idle at all....check your pcv valve, hose and put a tach on to see the idle....then go from there..oh and clean out your iacv valve too, thsoe things get dirty and cause iradic behavoir with your idle

lemme help you rephrase. low or uneven compression will change your idle to sit very low or idle erracticly. the vacuum test is conducted from a strong vacuum source from the intake mani. it would be easier if you already had a boost/vac gauge on. the 15 mins you spend on the vacuum test combined with the compression test is alot better than trying to troubleshoot with a hit or miss.

notice the idle dropped after a head gasket replacement. the compression test will make sure if its in the head gasket. the vac test will make sure and narrow down your search, because you may have accidently knocked something when putting the head back on.

you can rent these tools at your local automotive shops or go buy em. kinda expensive, but, its will worth it in my tool box, or, you can take it to your local mechanic to make it easier.

[polacek]

My civic has over 200k miles and I have not had an issue with the PCV. I would still agree with superbluecivicsi. If you want to do a simple vacuum test (just to show an example) disconnect a vacuum line while the car is running. An easy one to find is the line that hooks up to the cruise control. The car should quit running / be reaaaal sluggish.