motor setup is
B18 OBD0, crower 403s, B16 pistons/LS rods, ARPs, ACLs, cometic gasket(stock), crower valvetrain, cam gears @ 0*, stock OBD0 B18 intake mani, stock PR4 ECU

got my car runing the other week, valves were clearanced correctly(Crower specs) and started it up. it started fine, no knocking, no bad noises, but it would idle at 2500rpm and wouldn't drop.
ignition and cam timing is dead on, vacuum reads ~19hg, messed with the idle screw...no change, checked the IACV (used but was working 100% before the swap)...working fine, suspected the the fast idle valve being the culrpit(also working 100%before the swap)...still no change. I'm kinda perplexed as to whats going on.
now the car did take a while to warm up(has sat for ~2months, maybe??), so could the thermostat be bad and thus lead to screwing up the IACV and FITV operation and thus keeping the idle at 2500?? thermostat was fine as far as I knew before the new engine went in. so confused.... :x

any help is appreciated

 

Take the intake pipe off of the TB.

- There should be a hole in front of the throttle plate on the left side. Put your finger over that. If that slows the motor down then your IAC is letting in too much air.

 

I have the same problem with the CRX I just bought. It has a B16a from a Del Sol and the idle stays at 2500 rpm. I have cleaned out the IAC to no avail.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">Take the intake pipe off of the TB.

- There should be a hole in front of the throttle plate on the left side. Put your finger over that. If that slows the motor down then your IAC is letting in too much air.</TD></TR></TABLE>

 

bump because i have had the same prob and was wonderin what the hell it is.

 

Vaccum leaks? Manifold or Throttle body?

 

I tried the finger in the TB thing and it did indeed slow down the idle.
I have cleaned out the IAC and that didn't do a thing.

Do I need a new IAC ?

Thanks Guys!

 

^^yea get a new IAC

for the poster, if that didnt work...you need to make sure the IM gasket is sealing well, along with the tb gasket and bigger cams will also mess with your idle some, but not this much...

 

ANYONE KNOW A CHEAP PLACE TO PICK UP A IAC???

sorry for the caps. my bad

 

had the same problem-manifold leak..
but i would try what rocket said first..

 

idle air control motor or valve is a good plave to check but simplify your problem before getting into to more technical things like maybe a bad ground or so, just a thought

 

heh, you guys were right...although the cars been running for about 2 months now, there was indeed a huge pinch in the IM gasket, got a new one and she ran like a charm...the higher CR and 403 have the car running like a dream!!

 

I had the same problem with my b16a eg

all that was wrong with it was the throttle bracket and cable was from the d series, just bought a type r bracket and cable and its all good

do you have the correct bracket for the intake manifold? may be having to much stress on the cable

**** nevermind just saw your post about it working hah