fluctuating idle, pissin me off!

[94tegRS]

ok, my HB just started doing the whole idle fluctuation thing which is REALLY REALLY annoying. now Ive had a B18, B20, D15, and a ZC in this car, and each ones been out at least 2 times, and everytime I put them back in they would idle liek this til I bled the head and then it idled fine forever. but this time when it started doign it, I bled the head just to see (sold the car and repo'd it a month and a half later, sop who knows what its been through, although didnt start idling shitty til I owned it 2 days) but it didnt get it to idle, I pulled off the neg cable for like 10 minutes to reset the ECU and see if it could re-learn an idle or something, but nope. so I unplugged the MAP, TPS, and IACV and funny thing is it idled PERFECT like this. actually idled perfect with just the TPS unplugged but I unplugged em all figuring maybe I can make the ECU not see all 3, reset it plug em in and it will re-learn it all and idle, but once again, nope. the CEL doesnt come on though, but could the TPS/MAP/IACV still be bad, just not completely F'd? my TPS isnt screwed on like some ive seen, looks riveted or something so it wouldnt be able to shit or anything telling the ecu to idle LOW and then it catches itself about to die and kicks it up repeatedly could it?

what should I check. I already tried a (working a year ago) IACV and it didnt fix it. Im thinking about trying to find someone to let me swap out complete TB's with em and see if its the TPS. dont see how the MAP would affect idle but who knows and this will test that as well. will OBD1 civics TB's work? like will they bolt up to a b18b intake manifold?

[superbluecivicsi]

voltage test TPS, MAP, and IACV.

[94tegRS]

and this is done by??? I am sure I can figure it out, hopefully my chiltons has the voltage specs and test procedures in it, and this is if I can finally find that damn book.

[superbluecivicsi]

using a voltage meter from walmart. $14.99. best investment you can make.

your chilton will have the specs. if it doesnt, then, it is not a very good book

[sohcfreak97]

un-pluging your tps @ idle shouldn't really do much, since at idle your tps reads 0v +\- .5v's...did u check for any cracked or disconnected vacuum lines...sounds like it might have a leak some where, how many mods do you have done? my y8 used to have a jumping idle w/ all the aftermarket b/s i put on it...i just cleaned out my iac, and set my tps...0v at closed throttle...and 5v @ wide open

[94tegRS]

well, I only have intake and exhaust on the B18B thats under the hood. I checked for disconnected vacuum lines, didnt check for cracks good yet but did a quick inspection of the vaccuum lines and they seem fine at first glance. Ill check a little more thorough tomorrow. I have to drill out the TPS and tap the holes if I want to be able to rotate it ot change the voltage readings, which I might do tomorrow as well. I have installed a new/used IACV and it didnt fix it. didnt clean it though, was gonna take the screen out and clean it but it wasnt coming easy so instead of damaging it I left it in and scraped it good as I could and got it pretty clean. could I just soak it in some kind of solution for a while and then rinse it and l;et it dry or will the electonics in it get damaged?

[sohcfreak97]

try settin ur idle screw? sometimes if its too low, or too high, it'll jump around

[94tegRS]

well, the throttle stop screw hasnt moved or been changed, so I dont see how that could be the problem because the problem just arose one day. I am going to have to say its the IACV and the one I tried is just old and worn or damaged as well because I have searched and found a few threads where they say if you let the car overheat it can damage the IACV and when I repo'd the car it had a gallon jug of water in there. maybe he had gotten it hot ondce and then kept the water in there just in case. not sure whay the problem wouldnt have started right then though. but I doubt hed bled the head if he had overheated it, and maybe the air in the system eventually damaged it, I have bled the head since though hoping it would solve the problem but it didnt. I think I might just take it ot honda and tell em to test all my sensors but dont replace anything, just tell me which one/s it is.

[civickiller]

surging is usually

1. vacuum leak
2. air in your cooling system
3. iacv clogged and need to clean the screen off
4. fitv. take off cap an screw it in

usually if you eliminate all 4 of those, it will idle good again

[S13wanabe]

I'm not sure if the abreviations here already hit this, but I had a similar problem on my civic. I took off the fast idle control valve and upon opening it found that the plastic piece that srews in was screwed all the way out. I screwed it back in and the problem was solved. It's located under the throttle body. Good luck.

[civickiller]

thats what the fitv is

[94tegRS]

man I hope thats the problem, havent been able to get under the hood to chekc anything lately, hopefully I get some time soon.