So I recently bought a 96 civic Hatch cx. Runs great when its cold... after about 4-5 minutes the idle goes up and down dramatically. If I step on the gas to like 2,000 rpm (my prediction) idle does not fluctuate. Tried turning the car off and back on, still same thing. If I let it cool down and start it back up ides normal.

I've checked
-spark plugs (new)
-spark plug wires (new)
-distributor rotor (new)

I have read some post online about bad Idles on d16.
They were to check or replace
-IACV
-New intake Manifold gasket.
-Bad cat

What should I do about this? Appreciate all your inputs.

 

try clening the IACV on the back of the intake manifold.

take it off
Spray carb cleaner/fuel inj cleaner inside and on the screen till runs clear
let dry
re assemble


theres plenty of writeups on this if it seems confusing.

 

Thanks I will try this. Does it require a new gasket if I take it out?

 

nope. its just an o-ring and is reusable if its in good condition.

google it.

 

https://honda-tech.com/forums/acura-integra-6/%2A%2A%2Ahow-clean%2A%2A%2A-your-iacv-k-idle-air-control-valve-1575913/

 

Opened it this morning did some cleaning to the IACV and it idles smooth. No more jumpy idles