Ok, I'm not quiet sure what's causing this.. But it's starting to get real irritating.

When coming to a stop, My RPM drops more then it's suppose to. At times it actually touchs the 0 mark, other times it stalls out completely. Completely embarrasing when it dies out in traffic on the freeway and everyone around you thinks u stalled =\ anyhow.. if it doesn't stall, it may touch 0 and bounce back up to 750 or so. Now to make matters more confusing, when i turn on the headlights the idle drops to 500 and stays there, it may or maynot drop more if i turn on fan/heater. On average, the idle drops to 500 without headlights on but with heater on. Adjusting idle screw seems to do nothing. This is on a JDM h22a swapped into a 94si. I'm stumped.. any help appreciated. thx

 

Last time I had a problem like that, it turned out to be my alternator. You should definitly look into this possibility.

 

hmm.. all give it a check..

i've also heard a possibility could be the voltage regulator? anyone know anythin about this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by puffxy &raquo;</TD></TR><TR><TD CLASS="quote">hmm.. all give it a check..

i've also heard a possibility could be the voltage regulator? anyone know anythin about this? </TD></TR></TABLE>

Electrical Load Detector possibility,but highly doubtful? Did you check and see what kind of voltage you are getting from the battery when engine is running, with/without a Electrical load? And the Voltage Regulator is built into the Alt.

 

Ive had that same problem except it would kinda go away after driving 10-20 miles, sometimes i would stall at the light sometimes it went really close to 0 then bounced back up. after awhile my t-belt got shredded, replaced it with the manual tensioner and PE superstrong timing belt and the problem completely went away. yorus could be a diff problem tho, but same exact symptoms.

ps. i have crower ti retainers, ferrea valves and crower valvesprings, the stiffer springs i think can make the cams harder to turn , i think the autotensioner couldnt handle it

 

"Unplug your Idle Air Control Valve (IAC), which is located on the front of the intake manifold. Doing this SHOULD cause the idle speed to increase if it functioning properly. If it does not increase, then you have found your problem... go get a new one. If the idle speed does increase, begin to turn the bypass screw on the throttle body and bring the idle of the car down to like 500-600 rpm, then plug back in your IAC valve. This should bring the speed back to a normal 800 or so rpm."

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Cottonwoodz &raquo;</TD></TR><TR><TD CLASS="quote">"Unplug your Idle Air Control Valve (IAC), which is located on the front of the intake manifold....</TD></TR></TABLE>

anyone wanna help me find this?

and a side note: when i got the swap, the shop suggested i replace the alt/ac belt.. when i brought back one they claimed it was an inch too short, but they managed to "make" it fit... would this have an affect at all?


Modified by puffxy at 3:20 AM 12/17/2003


Modified by puffxy at 3:21 AM 12/17/2003

 

I had something similar happen to me... but the reason it was doing it, bafflled the crap outta me. It was back when I was taking my car into Honda to get service. They did a valve adjustment on my car, and adjusted them to H23 specs. So... when I drove my car and it was just warming up, it would stall. Also, while it was warming up, the idle would go between 1100 and 1400 rpms... very annoying to listen to. When a buddy of mine and I checked the valve clearance, and there was none... We readjusted them, and the car ran like a champ.

Also, check your IAC valve and see if its covered with carbon. It could be choking your car too.

Good luck

 

sorry for the newbie questions, but um... where's the IAC?

 

check alternator and IAC.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by puffxy &raquo;</TD></TR><TR><TD CLASS="quote">

anyone wanna help me find this?

and a side note: when i got the swap, the shop suggested i replace the alt/ac belt.. when i brought back one they claimed it was an inch too short, but they managed to "make" it fit... would this have an affect at all?


</TD></TR></TABLE>

Ok, I know exactly what your problem is. My first response said alternator, however, with your reply, I second my response. I'll tell you why. When they used a belt that was too short for the alternator, I'll bet it busted the bearings in the alternator itself (this has happened to me, that's how I know). When a belt is put on too tight on an alternator it will screw things up in a hurry. Do this for me though. Pop your hood and look at and around your alternator. If you see anything that closely resembles vasoline, it's a dead giveaway that the alt is messed up. I had this EXACT same thing happen to me, and everything you've said corresponds with the problems I had.

 

what about just a rough idle period . . . . I got a boost d16z6 and recently I have seemed to be having idling problems. My idle will go up and down (irratic idle) and sometimes when I stop at stop lights the idle will start to go from say 6-700-ish down to the point where the whole car starts shaking and sometimes even dying out.

I just recently cleaned my IACV valve and that seemed to help out a lot, but it didn't fix it 100% it just made it happen less. I am running dsm 450's with a 14b turbo, and hf manifold . . . . I still need to double check my vacuum lines and what not, but is there anything else that could be causing my car to idle this way?

It was never like this before I was boosted, and it wasn't like this when I first started boosting. Any and all suggestions are welcome.

tyson@genxperformance.net
aim:vtec92civic

someone help!

 

("Vtec92Civic" For a civic right?) Anyways this is how I am going to fix my problem, I think it is the timing belt. I swapped a JDM f22b DOHC in my Prelude and it ocassionally has the rough idle at start up. And sometimes if not running for a few hours then driving it, it would stall and the oil and battery light would come on. Not really sure but my mechanic replaced the timing belt with a usdm h23a. He said I should look into finding a genuine f22b JDM honda timing belt. And this problem should not occur anymore or do I have a bigger problem on my hands?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93cherrybomb &raquo;</TD></TR><TR><TD CLASS="quote">

Ok, I know exactly what your problem is. My first response said alternator, however, with your reply, I second my response. I'll tell you why. When they used a belt that was too short for the alternator, I'll bet it busted the bearings in the alternator itself (this has happened to me, that's how I know). When a belt is put on too tight on an alternator it will screw things up in a hurry. Do this for me though. Pop your hood and look at and around your alternator. If you see anything that closely resembles vasoline, it's a dead giveaway that the alt is messed up. I had this EXACT same thing happen to me, and everything you've said corresponds with the problems I had.
</TD></TR></TABLE>

hmm.. is there a sure way of checkin if my alternator really went bad??

 

also, i first suspected it to be the alternator because my headlights would get dimmer at idle and brighten when i rev it up.. but then when i tried turning the sterieo off ther was no difference, and i have a 360w amp.. since then i ruled out the alternator.. but now i'm not so sure..

 

i thought u said the altenator belt was too short? why not a replace it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by puffxy &raquo;</TD></TR><TR><TD CLASS="quote">also, i first suspected it to be the alternator because my headlights would get dimmer at idle and brighten when i rev it up.. but then when i tried turning the sterieo off ther was no difference, and i have a 360w amp.. since then i ruled out the alternator.. but now i'm not so sure..</TD></TR></TABLE>

Hmmm.......now that's weird. I'm out of suggestions then........sorry.

 

How is it running powerwise? When is the last time you changed your fuel filter?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by biglew &raquo;</TD></TR><TR><TD CLASS="quote">How is it running powerwise? When is the last time you changed your fuel filter?</TD></TR></TABLE>

car runs strong, only problem is when it's idling.. more so when i'm coming to a stop. fuel filter was changed when i got the swap, 4 months ago or so..

 

Never mind then, I know that sometimes a clogged filter will cause the car to stall or almost stall during idle due to fuel starvation. But your all around performance would be affected to so I think that rules that out. Have checked your battery.

 

this will do it. it did for me

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jaesung &raquo;</TD></TR><TR><TD CLASS="quote">this will do it. it did for me </TD></TR></TABLE>

where is it?? anyone got a pic or something to show where the IAC is?

 

bling!

anyone?

 

It's on the intake manifold about center.

 

You might have a shitty alternator as someone said before. That will cause your car to drop and raise the idle, because the alternator can not handle the power. It looks like there is quite a bit of problem with the idle on the preludes. Hope this problem doesn't happen to me.