my d16z6 is idling terrible it jumps up an ddown from 500-1500 it my es motor mounts make it feel terrible it chatters like hell. it dosent do this when i first start it up but after i hit the gas it does. i checked all the vaccum lines i could find and they all seem to be in good condition.
thanks
chris

 

does it do it only when warming up or just until you hit the gas one time?

 

just until i hit the gas its not as bad when its warming up but when its warm its a bitch
thanks
chris

 

Check your coolant level. The fast idle of a FI Honda is controlled by an air by-pass valve. When the engine is cold, air is by-passed around the throttle plate and the idle speed is increased. On later FI systems an Electronic Air Bypass Valve was added, and it too adds air during cold operation. On some newer systems the fast idle is controlled entirely by the Electronic Air Control Valve.

These air by-pass valves are mechanical valves that are normally open when cold. As the engine warms up the hot coolant from the cooling system warms up a wax pellet. The wax pellet expands and closes down the air by-pass valve. For the air by-pass valve to work it needs to be heated up by the engine coolant. When the air by-pass valve can't get heated up enough (because the coolant level is too low) it can get stuck at the “threshold” point and the idle will race up and down.

If this valve is bad, it won't have any effect on cold engine operation. It'll only cause the "hunting" idle as the car warms up. BTW, if the coolant level is okay, check the by-pass valve itself.

 

i think your TPS is out of calibration. if you know how to use a volt meter check whats the voltage at with a voltmeter. and cross reference that number with what's written in the helms manual. i can't remember it off the top of my head.

 

Also in addition to what evryone else has said double check your cap and rotor. Sometimes the screw can back out on the rotor and cause the car to sputter when you hit the throttle. I have seen it before.

 

cool thanks for all your help i went to the my honda tech and he said that it could also be due to a over tightened throttle cable so first thing tomorrow i will check through everything
thanks
chris

 

i dont think an overtightened throttle cable would cause an erratic idle
if none of those things work check your gaskets on TB and intake manifold (dont actually remove the peices just look for visible cracks/missing peices on the gasket.)


[Modified by KAMiN, 6:48 AM 1/30/2002]

 

Please let us know what you find.

 

a good way to check for vacuum leaks is to spray carb cleaner around the gasket mating surfaces. if theres a leak the carb cleaner will be draw into the motor, and it will hesitate/stall. good luck

 

could also be the iac (idle air control).


[Modified by sohc_boy, 8:01 AM 1/30/2002]

 

FITV or Fast Idle Themo Valve

The ES inserts then to loosen the plunger about once a year.

I've had to tighten mine 3 times now.