Rough idle in "D" gears

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A

AccordSE

New Member
Hey guys, I have a H22a motor(auto) in my car. The problem is that my motor rpm drops down and then up, sounding like it's going to die for a bit and then not. This only happens on the "D" gears when I come to a complete stop sometime. I say it does this about 75% of the time. What could be the problem for this? Could it be that I need to clean my "fast idle control valve" and "Idle air control valve"? Help me out guys....
 
TPS, IAC, EGR. You'll just have to play with it. You can test your IAC by unplugging it. TPS, you need a voltmeter. EGR units can just get clogging underneath, fucking with your A/F ratio. You can raise your idle a bit, but that's more of a last resort. TPS is pretty common.
 
Sounds kinda like a vacuum leak...but if it's only in D then that kinda goes out the window. You could try cleaning the IAC. I had a Ford 302 and it ranged pretty bad while in gear. It was the intake air control solenoid sticking. EGR could cause this too if it wasn't closing all the way at idle...Does the problem go away once rpms go up?
 
Well, this does happens in "P" and "N" too but not much, only does it about 15% of the time when the car been driven for a few minutes. But when it's in "D", it does a lot. How can I check to to see if there's any leak? What do I use? How/what do I use to clean the IAC? Also, how should I unplug the IAC since it happens mostly on "D" gear only? Should I let someone drive it and leave it in "D" and then I should just unplug it? Whats the EGR and where is it located?
 
You unplug the IAC when the motor is running, and see if the idle drops. You can also adjust your idle up a little, and that is done with the IAC disconnected and service connector jumped.
 
Well, when my car is on(running in idle, warm up) and when I unplugged the IACV, the rpm drop from 700 to around 200 but did not die. So is that good or bad? However, when I cover the top hole inside the throttle body where the intake connects to, the car rpm drops and die. So is that good or bad also? What do you mean by service connector jumped?
 
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There is a two prong service connector inside the car under your passenger side dash that has to be jumped to adjust timing and idle speed.

It's good that your car didn't die, but I would say your idle speed is a little low. I think mine ran at about 4-500 rpms with the IAC disconnected.
 
it might also be your distributor ? I also have a jdm h22a in my 93 accord. When my brother swapped out his h23 with an h22 on his prelude, he was getting bad idling problems too. After he bought a chipped ecu, it kinda helped. It still revved up and down, but only when his engine was cold. But when he was running off the stock p13 ecu, his idling happended while cold or a hot engine.

As for me.. my brother-in-law switched out my jdm distributor with a usdm h22a4 distributor. He said that the jdm distributor has a coil or something that will cause the engine to rev. I do not have any revving problems what so ever on my car. Only time i had bad idle was when my vaccum hoses were not plugged and had bubbles in my anti-freeze. Im not sure if its acually the distributor, but it wont hurt to ask around. It works for me. =) .. I hope this helps you a little.
 
I've had both internal and external coil distributors. It doesn't matter which one you have. They can both have the same problems. They are virtually identical inside.
 
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