stupidfox

ok, I've been reading everything I can find on here about this, and trying it, and nothing, and from what I can tell, this problem can be a bunch of different ****. here's my story.

rebuilt the engine this winter (new crank). put it back in, got it running.

Problem: When I start the car, it idles around 2k for a couple seconds, then starts surging from 1500 to 2500.

here's what I've tried so far and the results. I'm just hoping someone can put this all together for me.

possible iacv. took it off, cleaned the screen. not fixed.

plugged hole in tb for fitv, not fixed

unplugged harness from iacv while running. idle steadies kinda, bounces from 1000-1200? short but still noticeable. possible cause?

fitv thing loose. took it off, thing was kinda loose, tightened it, not fixed

decide to steal parts from my auto 94 that idles well

swap tightened fitv and cleaned iacv from 94 onto the 95 im working on. not fixed

tps sensor- unplug. did it, idled at 2000 even but no surging at all.

so i'm guessing its some combination of the iacv and the tps?

i hoping someone had this exact or very close to it problem and can tell me what to try?

also the KS broke when i was fixing the engine, the wire is still connected just the plastic part is busted. would that be part of it?

and i don't think the timing is dead on either, so i'm working on that too.

i need to start driving this thing to work at 1am in a few days, only a few miles, but its all residential and i dont want cops waiting for me after the first night- if you can help it will be much appreciated.

mikemerc85

did you see if your intake manifold gasket is no good. My 88 prelude was doing the same thing. it would surge from around 1000-1500 to about 2000-2500. Then i popped my hood and while the car was running i heard a hissing noise coming from the intake manifold. So i took it apart and found that the gasket was bad. Fixed it and the surging stopped and ides perfect now.

stupidfox

hmm... that could explain the high pitch whining noise too... it sounds more mechanical though- like a loose belt.

i'll check it out tommorrow, but when i unplug the tps it idles fine, just higher than it should...

thanks, i'll check tommorrow.

TurboSI2nR

my car had the exsact same problem when i put it back togather, turned out to be the egr eliminator plate that i made, wasnt tight enough. it made a horible noise like a vacuum leak. that fixed the problem quick. but then a few months later it started doing it again and i played with some stuff and i changed my iacv and it never did it again. i have an extra iacv and egr valve if would like to try either of those. i would say iacv though. oh another reason i was having idle trouble at one point was my bleeder screw on the throttle body which is used to adjust idle, it was pretty much all the way out just sitting in it's place and was acting liek a vaccuum leak. good luck

ludebabe

have you done anything to fix the oil leak on the lude yet?

stupidfox

um... ive decided its not an oil leak, its just a cool new way to change the oil in a continual way... so thats a "not yet"

Ch3mik

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by stupidfox &raquo;</TD></TR><TR><TD CLASS="quote">hmm... that could explain the high pitch whining noise too... it sounds more mechanical though- like a loose belt.
</TD></TR></TABLE>


mine makes that high pitch whining noise like a belt too!! and it surges horribly. could it be the intake manifold gasket?

Hawkze_2.3

Definately not the knock sensor. Mone was completely broken off and all it did was throw a code.

Try replacing your IM gasket (preferably with a Hondata or similar), because those will get old and leak.

eluder33

my car had the same problem, try screwing the idle screw in a turn or to, it worked for me.

amckee

Unplug the IAC and set your base idle to between 500 and 600 RPM. When you plug it back in it should idle up to 750 or 800. Clear your code when your through. And put a little dab of silicone on the screw head to keep it from vibrating out and causing the same problem again.

Ch3mik

so the high pitched whistle noise is air escapin the manifold through a crappy gasket?

amckee

No.

manman

main reason for idle surge is vacuum leak check vacuum lines intake gasket anything to do with the vacuum system plug the vacuum leak fix the problem other possible reason bad ecu. if its making a sucking sound or whistle as u say then its a vacuum leak

Ch3mik

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by manman &raquo;</TD></TR><TR><TD CLASS="quote">main reason for idle surge is vacuum leak check vacuum lines intake gasket anything to do with the vacuum system plug the vacuum leak fix the problem other possible reason bad ecu. if its making a sucking sound or whistle as u say then its a vacuum leak </TD></TR></TABLE>

yea, it makes a fairly loud whoosh, lol. then when im drivin , it does a slight whistle. when I get home im going to try all the different things I read on honda tech today
(I spent 2 hours lookin through various idle situation threads )

nah22accord

Like mattman said. Mine was doing the same and I played with the idle adjust screw for a bit until it stopped.

XanderLude

Mine had this problem until I blocked a port on the TB. I had my FIV blocked too. If you take the intake off, you should be able to feel a vac leak when the throttle plate is closed. I just blocked that port off and my idle stopped surging.

Hope this helps someone.

SNsLude

I recently had the same problem you guys have had.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hawkze_2.3 &raquo;</TD></TR><TR><TD CLASS="quote">Definately not the knock sensor. Mone was completely broken off and all it did was throw a code.

Try replacing your IM gasket (preferably with a Hondata or similar), because those will get old and leak. </TD></TR></TABLE>

I took off my tb thinking it was my fitv because of the suction through the lower port in the tb. It turns out my fitv was bad, but in the act of taking off the tb (it was stuck the hell on there so I had to use a mallet to get it off), my IM brewed a leak. Turns out my IM was warped and so I had to get it ground down and make a new gasket.

If you can clearly hear a whistleing sound it is most def a vaccum leak. Check all vac lines. Spray carb cleaner all around your IM and try to pin point the vac leak that way.

Also, another source may be bubbles in your coolant system. You could try leaving your coolant cap open for a while to let the air settle out or slightly unscrew the coolant bleed bolt and see if bubbles come out from there.

gooood luck... surging idles can be a pain in the ***. take it from me, I've tried most likely EVERYTHING trying to trouble shoot my problem till I finally got rid of it. =[

SNsLude

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by XanderLude &raquo;</TD></TR><TR><TD CLASS="quote">Mine had this problem until I blocked a port on the TB. I had my FIV blocked too. If you take the intake off, you should be able to feel a vac leak when the throttle plate is closed. I just blocked that port off and my idle stopped surging.

Hope this helps someone.</TD></TR></TABLE>

Hope you rerouted your coolant lines when you blocked off the fitv. You can take full advantage of blocking it off if you reroute the coolant lines instead of just blocking it off for a vac leak

XanderLude

twas the actual reason I was getting a surging idle. I did a complete coolant bypass to the IM.

Ch3mik

I finally got the surge to go away, tightened up the white plastic screw thing beneath the TB. now it just idles high. the idle adj screw is all the way tightened too, but I hear the high pitched whistle sometimes so im 99.9% sure theres a vacuum leak somewhere. I replaced the TPS as well cuz i noticed the one on there was cracked in many spots. no more surging at least. you guys think its my IM gasket?