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So I've been having a problem with my 2004 Civic EX. Symptom 1: The car idles normaly but If I give the car the slightest bit of gas the car revs all the way up to 2k rpm and then comes down. symptom 2: And if I rev it up further then 2k myself and let off it will fall down to 1k and then bounce back up to 2k and then down and idle normal again. Symptom 3: it I'm on the highway and I put my car in neutral while crusing the engine will bounce up and down from 1 to 2k over and over untill the car stops rolling. Things I've done: I have cleaned my TB my IAC my EGR and checked for vacuum leaks best I could. I changed my Coolent temperature sensor and my MAF sensor. Does anyone know what this problem could be? I have no codes accept one from my cat delete.
To me it sounds like a dirty IAC, I know you said you cleaned it but the inside is not easily done. How did you go about cleaning it?
I took it off and sprayed it with carb cleaner and whipped it with shop towels and q-tips until I got all the carbon build-up off its shiny in there. After that didn't work I even swapped it out with the one from my old engine that I also cleaned. Changed nothing
You can try removing the drive assembly portion of the valve. I believe the screws take a special 5 point bit though. That will allow you to spin the rotary valve by hand to feel for resistance, it should spin freely.
You can also try unplugging the IACV and see if the idle still surges.
You can try removing the drive assembly portion of the valve. I believe the screws take a special 5 point bit though. That will allow you to spin the rotary valve by hand to feel for resistance, it should spin freely.
You can also try unplugging the IACV and see if the idle still surges.
Yeah I've tried it with the it unplugged and it doesn't surge. But I will try taking off the drive assembly and see if it's gunked up or not. Thanks!
Honestly I don't think you can clean it well enough without being able to spin it by hand. The last time I cleaned one I had it soaking in cleaner while spinning the valve, still took every bit of 45 minutes before it was free enough for my liking.
The alternative is to simply replace the IACV. I would recommend Honda genuine parts though.
Honestly I don't think you can clean it well enough without being able to spin it by hand. The last time I cleaned one I had it soaking in cleaner while spinning the valve, still took every bit of 45 minutes before it was free enough for my liking.
The alternative is to simply replace the IACV. I would recommend Honda genuine parts though.
Yeah I took a look at it and the bolts are really stripped, not sure if I wanna tackle that or not. Another wierd thing I just noticed is that it doesn't do the idle surge for Like the first 30 seconds after I start the car. I can press the gas and then engine revs up and down normally, And then suddenly it starts doing it again. So this problem is intermittent witch makes me think maybe it's an ECM problem?
Yeah I took a look at it and the bolts are really stripped, not sure if I wanna tackle that or not. Another wierd thing I just noticed is that it doesn't do the idle surge for Like the first 30 seconds after I start the car. I can press the gas and then engine revs up and down normally, And then suddenly it starts doing it again. So this problem is intermittent witch makes me think maybe it's an ECM problem?
I cleaned out my IAC completely until the valve would just flop around on its own, still no difference. I'm really at a loss here I've been trying to figure this problem out for months now and to no avail.
