C/P from Honda-tech:
My hatch has been having issues with loping idle. The idle fluctuates 300-400 rpms (best
guess as I have no tach).

Im really at a loss on what to check. Ive read that sometimes air in the coolant can cause the IACV to stick. I bled the system and even replaced the IACV with no change. There is no FITV, there is just a passthrough at the bottom of the TB. Its all one piece on the TB, not added. Is there anything else it could be assuming its not the FITV? Do these motors come without a FITV?

Also to note that it only fluctuates after the car is warm. However, if the car is warm and you shut it off/turn it back on, it will not fluctuate until you tap the throttle..

It will not fluctuate when cold, it gets progressively worse as the car warms.

I have been searching for a used TB with the FITV attached but no luck.. Will the D15B7 Intake Mani/TB fit the D15B8? Would there be any complications, CELS etc from running this IM/TB instead of the B8 IM?


Thanks for your help

 

the fitv wont be the problem if it only does it when the car is warm.
have you checked to make sure theres no small holes in hoses, vaccum leak somewhere?

 

+1 vaccum leak

 

Ill start checking leaks when I get home.. anywhere you suggest to look first?

 

should be able to google images where all the lines are, that will be the easiest

 

So it wasnt a vac line.. it was a 3 inch gaping hole where part of my intake manifold gasket is missing.. holy crap!

 

lmao