I have had a 1994 b18b1 integra engine swapped into my del sol. Ever since it idles at 2000 rpms and fluctuates up and down from 1700 to 2000 on a cold start. After i drive it for a few minutes it goes down to around 1000-1100 rpms and drives fine after that. It will occasionally go up to 1300 for a few seconds and back to normal. Most of the problem is when starting the car though after it warms up it drives good.

I have been doing research for a while and replaced iacv, cleaned throttle body, cleaned the fitv and replaced it ,also screwed the pelet tighter, messed with he idle screw, bled the coolant.
And today i changed the whole throttle body( used the one from my cousins b18b1) and it idles even worse. I tried checking for vacuum leaks by using brake cleaner, didnt find anything.
One thing i did find was when i i removed the cold air intake , i plugged the bottom hole in the throttle body nothing happend, but when i plugged the top hole it dropped rpms and idles regular .
Also if it makes any difference, i changed the old valve cover with a new b18b1 valve cover and i plugged the pcv valve on the valve cover.

Im stuck.Any suggestions?

 

bump.. need help! Another thing i forgot to mention is i just recently found out im running on an automatic p75 a51.. i have a feeling this might be the issue

 

Do you know ayone that wil let you borrow their manual ecu to test it out with?

 

And the uper hole that you plugged I think is for the map sensor

 

Yea im trying to find someone! Idk it might be for the map sensor but i changed the whole throttle body with sensors and everything and it was still the same so i doubt its any of those sensors.

 

lol. the 2 holes are passages for iacv and fitv. the lower is fitv and upper is iacv. by plugging the iacv passage and idle smoothing, you have detrmined the problem to be iac related. that doesn't necessarily mean the iacv is the culprit. the iacv is just an actuator operating on the ecm's command. the ecm has many inputs for iac regulation. of which any one could be causing your problem.
have you had the batteries disconnected recently? or had the ecm fuse removed?
if so, you need to run through an idle relearn. that is, allow car to idle for 10 minutes UNDISTURBED.
if that's not the case, start by checking for codes. regardless of an illuminated cel.
if none present, service the iacv PASSAGE. with the intake boot off, engine running, spray liberally, with the nozzle straw, directly into the upper hole with intake cleaner while pulsing the throttle with your other hand. you want to really let it saturate that passage. it's common for carbon build up in the passage to skew iacv performance.
next, idle adjustment. this plays a huge role in iac operation. people often adjust idle incorrectly and this actually causes a lopey idle.
follow this method EXACTLY as stated:
vehicle at operating temp, disconnect the iacv. idle should drop to approx. 500rpm. if not, adjust the idle screw until it sits at 500rpm. reconnect iacv. engine should now idle at roughly 750rpm. if so, clear the iac code and allow idle relearn.


start with those items, in that order, and report back

 

Sprayed the upper hole and did the idle relearn and still the same. Im starting to think its the auto ecu im running. It doesn't throw any codes and runs pretty good after 5 minutes. I bought a manual p75 online today so im going to try that next.

 

Had the EXACT same problem with my 16a. change the throttle body, IAVC and clean clean clean etc etc and had the same problem.. decided to just "live with it" and lost compression in cylinder 1 and 4.... did a full swap to a b16b but had to wait for the ecu...temp ran the p2t ecu and still had the same problem...once i got the pct ecu problem disappeared. Def change the ECU and Prob will be gone!! :D

 

are you sure you got everything out of Iacv, had to do mine twice. also did you put your heat on full while Bleeding coolant? could be air in system


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So i finally put in the right manual ecu. It the Fixed hunting idle and shifts WAY smoother. But high idle still remains on cold start! ill try cleaning the iacv again and yes i bled the coolant.

 

Disregard that last post. Everything runs perfect now. Car idled high for a few days then i guess it adjusted itself. No more annoying high idle =]
Culprit was auto ecu in manual car!

 

sounds like a idle air valve is bad