I have a 94' B18B1 swapped into a 95' EG 4dr. Motor came out of a 94' automatic teg. I have no CEL. Replaced the IAC motor twice with used ones. Cleaned the screens with carb cleaner on both before replacing them. Replaced the coolant temp sensor with a brand new one. Still has a rev bounce at idle. Any other suggestions will greatly app. It's super annoying. Thanks

 

Play with the timing, theres various ways - one is by twisting a screw on your throttle body that alters your air ratio. Another involves a timing light, and there are other ways. It more or less needs a good tuning, not "tune-up" spark plugs, etc., tuning essentially gets air/fuel/spark all applied perfectly so that it idles smoothly. Thats just my opinion - and my other 8 cents, find someone and pay them to do the tuning, they will have all the tools and know-how.

 

Are you sure you don't have a vacuum leak? Spray carb cleaner on all vacuum hoses, vacuum ports, and gasket areas like the throttle body and intake manifold. If the idle suddenly changes you found the leak.

Also do a search for "fitv". It stands for fast idle thermo valve and it's under the throttle body. There is a ton of info about how to clean and adjust it.

 

adjust the iac open it up and screw it all the way down than turn out two turns and and see what it dose

 

Remove your air intake and cover the hole in the side of the throttlebody if the idle smoothes out then your problem is in that area if it still idles with a surge then it could be elsewhere.
What ECU are you using?
Sometimes the car has to be taught to idle again.

 

I will give the IAC screw turn down a try. I'm using a p75 ECU.

 

i had 00 civic ex and it did the same thing and it was cause it had a automatic throttle body i put a manual one on it and it quit

 

at what rpm is it doing it at

 

At idle it bounces from 1,500 to 2,000 and back down.

 

Is the ecu from a automatic?

 

I'm 90% positive it is a manual ECU. It is a p75. How can you tell the difference by looking at the ECU if it is A/T or M/T?

 

help

 

check the wire hareness that goes to the iacv and make sure its the right one cause two plugs are the same and to check if your ecu is manual or auto call honda and tell them the number on the ecu and they will tell you

 

Ok, cleaned the IAC. Cleaned and screwed down the FITV. And I cleaned the throttle body itself, butterfly and holes leading from it as well. Pulled the 7.5 amp fuse under the hood before I started, replaced it when I was done. Stillllllllllllll I have the Rev bounce!!!! If I had a A/T ECU, then I would assume I would have some sort of CEL because it would be looking for A/T sensors that are clearly not there. But I have no CEL's. Does this mean my Automatic throttle body has to go?

 

do u have a a/t throttle body that will cause it to do that if u use a manual harness

 

Yes, I do have a A/T Throttle body. I just cleaned and screwed in the valve inside what the red arrow is pointing to today. Guess I need to buy a manual throttle body then. Thanks

 

manual and auto obd1 ls throttle bodies are the same.

 

get a manual h22 throttle body its bigger and will bolt right up. and if your ecu was auto it will throw a cel code 19. the auto vs manual throttle bodies are diffrent.

 

I have no CEL codes. The only explanation for having no CEL that I can think of. Would be that I might have a A/T ECU and having the A/T throttle body would cause no CEL's to show up. I know I have a A/T throttle body for sure. Have to call an Acura dealership with the #'s off the ECU to find out for sure yet. And what is a code 19? Thanks

 

a/t ecu still has to control a a/t shift points and if it doesnt detect the seloniod the cel will pop on which code 19 a/t failure or something along thos lines. i know this cause I chipped a p06 ecu and didnt know it came from a auto car. so that rules out your ecu get a m/t throttle body and it should fix your problem.

 

Ok, I replaced the 94' automatic throttle body with manual 00' throttle body. My car still has the idle rev bounce. There are zero vacum leaks. Could my PCV valve be acting up? When I replaced the head gasket, I removed the intake manifold from the head. During removal, the black softish/hard line running from the bottom of the PCV valve to the OEM oil canister/catch broke. I bypassed the plastic elbow like piece in the middle of the intake manifold. I just ran a piece of hose from the top of the intake manifold directly to the oil canister/catch. Could the plastic elbow piece have something to do with my idle bounce? Thanks, any help would be greatly app.

 

its the IACV. its either the wiring going to it, or the valve itself is no good. they DO go bad and thats why they're a rare find at the junk yard. check the wiring and if u are 100% sure the wiring it correct and/or good, grab another IACV and put it on there.