When idle drops?

[mySICKOcb7]

Lets say your infront of my motor (H22A) , when you manualy give it gas, the car revs up and when it comes down, it drops below 1000 rpm to like 500 and if you quickly give it gas again while its down in the 5/6oo"s, it makes like a valve tap noise in the motor. Don't know what it is but need some help.

[manny_turbo]

hey my f22 does the same thing but mines like a louder tap sorry for stealing thread

[mySICKOcb7]

I want to know badly what that is, and how to stop my idling from dropping 1000 rpm's after pressing the gas.

[zack_odom]

Uh...Your guys' cars are supposed to idle at 750-500 RPM.
Ur welcome lol. And as far as I know the tap noise is normal.

[PowderedMilkMan]

I believe the tapping noise is your valves, you have 16 of them. You might want to adjust them or get them adjusted if you haven't routinely tuned your car and your car is around correct Idle speed, I'd check your manual just to make sure correct idle speed because it varies between the USDM/JDM/EDM models and if it is auto or manual.

[mikesCB-7]

I want to know badly what that is, and how to stop my idling from dropping 1000 rpm's after pressing the gas.

my vote is a good tune up..... any valve ticking at idle? how many miles btw???

EDIT: Spark plugs, wires, oil (oil filter), fuel filter, bad ground possibley, and check them vacuum lines.

[NAiL05]

1. Idle Rpm is supposed to be 750 +/- 50 RPM not 500.
2. Honda's are notorious for valve tap. If its excessively loud depending it could need an adjustment.

[zack_odom]

+1 /thread.

[BillKisme]

My rpm's use to drop below 500 and seems like the car was going to die. I found out my TB was really dirty so I had it cleaned and I have no problems anymore.

[h92ex]

i usually let my car sit from 2-5 minutes depending on the weather when i first start it to warm it up, and it idles at like 1.5k rpms..after i drive around for a bit when i first noticed it being that much i put it in park at a stoplight and it idled at around 750...this is of course me assuming idleing is just when ur car is in park and not moving hehe

[F22-GURU]

Lets say your infront of my motor (H22A) , when you manualy give it gas, the car revs up and when it comes down, it drops below 1000 rpm to like 500 and if you quickly give it gas again while its down in the 5/6oo"s, it makes like a valve tap noise in the motor. Don't know what it is but need some help.

Without knowing the mechanical state of the engine it may only be a Pre-Ignition/Detonation noise from the engine.
On deceleration the Engine Computer automatically adjusts the ignition timing and cuts fuel injector operation to prevent excess emissions on decel.
The Computer receives signals from a number of engine sensors to let it know what run condition it is in. Idle, Accelerating, Decelerating (With & Without Load) etc.
The computer then references Pre-Programmed Fuel & Ignition Maps to know the exact amount of time the fuel injector needs to open/closed and how much the timing needs to be advanced/retarded in relation to the specific run condition at that precise moment.
When you Snap Accelerate the engine from a normal/stable idle condition the computer recognizes the run condition and adjusts as necessary without abnormal nosies.(As long as engine tune is in spec)
As stated before when the engine goes into a deceleration condition the computer cuts the fuel and timing to suit and it's the suddenness in run condition from a Near Stall Condition to a Snap Acceleration Condition that causes the Computer to suddenly readjust Fuel Delivery and Timing Advance which causes the fuel mixture in the combustion chamber to detonate prematurely.
Note: Fuel Quality can also affect engine conditions.

...or it could be rattly just tappets.

Cheers
Geoff