Hi I haves quick question, I had to take off my intake manifold on a b16a to replace the knock sensor and everything goes well until putting that thug back on, it's one of those skunk2 ones so the casting on it is deeper and had to replace the gasket, anyways, when everythings back on it idles high and unsteady, from about 1-3k tops. I tightened the top bolts on it some more and the idle dropped about 500, I'm guessing it's a leak? I know this a lot to read but thanks a million if I record any sort of help :D thanks!

 

Did you unhook any coolant lines? If so you'll need to bleed the coolant system. Double check everything is installed properly. Make sure you didn't mix match your tps and map sensor. Check for vacuum leaks.

 

Vac leaks are 99% of the reason a d/b/f/h will have idle problems. If there was *any* gasket residue left on the IM or head, there's a good chance it will leak enough vac to cause unsteady idle. FITV-equiped cars will occationally need that white disc tightened, but it won't cause an idle issue overnight.

Disconnect the IACV (or plug it's hole inside the TB) and it should settle to a barely running idle of around 400rpm. With some aftermarket cams or TB's it may be 700-800rpm at the lowest. You are supposed to adjust the big brass idle screw (not the pulley stop) to attain 400rpm or closest to it.

If idle w/o no IACV a is much higher, you have a vac leak somewhere.