this is the iac off my gsr. my understanding (and from what i saw on my "new" one) is that you should see a white plastic big screw thread lookin thing in that second hole and that this indicates my plunger type thing is stuck plunged. we replaced it with something labeled "90 civic" now i'm starting to wonder. i can see in my helms technical drawings that the B18C and B18B look different and have slightly different hose inlet tubing (B18B doesn't curve left like that, but i don't think this detail is all that important). the drawing makes the B18C look bigger and beefier. i guess now i'm wondering exactly how interchangable these things are since now i apparently have one off an old civic and whether this piece (above) is broken since replacing it didn't immediately fix the problem. tia and junk.

 

The IAC is an electrical-mechanical part. There's no way to just look at it unless you see physical damage. Check your Helm's manual about checking this unit.

 

ok. let me ask my question another way: does anyone see physical damage?

 

I just took my iac valve off the other day and it had that white screw looking thing in the second hole.

 

That white screw may be just a sleeve..
older carbs had a sleeve on the secondary "plungers" that would deteriorate with gasoline.. to fix that sticking plunger we would remove that sleeve without any harm done..
just cause it aint there may not mean a bad thing, maybe it wasnt incorporated yet in that year..