ludelvr

Okay, I've spent the last 2 nights reading archived posts and threads on this topic and I've tried a few things out but nothing seems to be working. My idle never falls below 1000 and most often it sits at 1100-1200. After accelerating I let of the gas and sometimes the idle will drop to 1000 but then find it's way back up and then it will drop back to 1000 and then go back up to 1200 or so and then it will situate itself back at around 1100. It's like it's trying to find a good idle and sometimes it does and it'll stop.

Also, I am hearing what seems to be a vaccum leak, it's a really loud hissing sound coming from around the stock fpr vaccum source but it doesn't seem to be leaking from that.

Things I've tried so far is taking off the iacv (which is on the front of the intake manifold inbetween the intake manifold and valve cover) I took that apart and cleaned it, there was a **** load of stuff on that little filter. I also tried resetting the ecu, I tried lowering that little screw underneath the throttle rotor so it would idle lower, I tried tightening and loosening the throttle cable but none of this seems to be working.

I'm fine under boost and there is no hesitation or anything, just torque but at idle, whenever it feels like it, it'll start bouncing. Never stalls but that hissing sound is starting to scare me. Anyway, I couldn't find anything else that could help me in past threads but maybe I'm missing something. Oh yah, one final thing, my a/f autometer gauge is acting all wonky, it suddenly is always at red and when I floor it, sometimes it will read almost all the lights on at once, but most of the time it looks dead. After I noticed this, my check engine light came on and then I shut the car off and it hasn't come back on since, but the gauge is still whooped. Any ideas.


Modified by ludelvr at 8:02 PM 4/17/2003

MiraiZ

um...I think you've ansewered you own question...check for vacuum leaks?

ludelvr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MiraiZ &raquo;</TD></TR><TR><TD CLASS="quote">um...I think you've ansewered you own question...check for vacuum leaks?</TD></TR></TABLE>

I have been checking for vaccum leaks but to no avail. That's why I'm kinda wondering if anyone knows what vaccum line would cause an erratic idle/high idle if it were leaking. Is the erratic idle a cause of the vaccum leak or are these two isolated cases?

censored

I had the problem forever after I swapped engines, I cleaned everything checked vacuum lines over and over, reset the ECU, blah blah I finally got down to just replacing the whole intake manifold/TB from my old engine, the problem was, the engine I got came with a broken TPS sensor so I just took it off my old set up and didn't line it up when putting it back on , I didn't realize this until I had the back side of the engine tore apart, all that time and all that trouble just because something was misaligned, so if you have replaced anything double check to make sure everything is line up accordingly

MiraiZ

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

I have been checking for vaccum leaks but to no avail. That's why I'm kinda wondering if anyone knows what vaccum line would cause an erratic idle/high idle if it were leaking. Is the erratic idle a cause of the vaccum leak or are these two isolated cases?</TD></TR></TABLE>

All of them would...anything that would feed the engine an uneven stream of air like a vacuum line with a leak, will cause the engine to idle high and irratically.

ludelvr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by H-T Member &raquo;</TD></TR><TR><TD CLASS="quote">I had the problem forever after I swapped engines, I cleaned everything checked vacuum lines over and over, reset the ECU, blah blah I finally got down to just replacing the whole intake manifold/TB from my old engine, the problem was, the engine I got came with a broken TPS sensor so I just took it off my old set up and didn't line it up when putting it back on , I didn't realize this until I had the back side of the engine tore apart, all that time and all that trouble just because something was misaligned, so if you have replaced anything double check to make sure everything is line up accordingly</TD></TR></TABLE>

Yah, I haven't taken anything off, with the exception of the IACV, but once again, I'm leaning towards the vaccum leak because of that very loud hissing sound, but again, it's only at idle because I am capable of getting boost, so I'm wondering if the idle is a cause of the vaccum leak or if the vaccum leak is a separate thing, but from the sounds of it, the idel is in fact a result of the leak

DTSbmxKID

i put a b18c1 in my del sol and i hooked up the wrong connector to the map sensor and my car idled like ****. it did the same bouncing behavior your talking about. If you still have your map sensor plugged in to the box on the firewall you are wrong. on a gsr harness there is a plug coming straight off of the wiring harness to plug into it. im not sure what setup your running but maybe this might help some swappers get their cars running right.

censored

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

Yah, I haven't taken anything off, with the exception of the IACV, but once again, I'm leaning towards the vaccum leak because of that very loud hissing sound, but again, it's only at idle because I am capable of getting boost, so I'm wondering if the idle is a cause of the vaccum leak or if the vaccum leak is a separate thing, but from the sounds of it, the idel is in fact a result of the leak</TD></TR></TABLE>

my car would hiss very loud at idle too, sounded like it would suck up small rodents if they got too close, it sure did impress the ricers though

Tegman88

hey whats your setup? I'm having a similar problem...I think its due to my DSM 450 injectors, but not too sure...sometime during startup...I have to crank and give it some gas...after it warms up a bit, the idle is kinda high...maybe around 1200-1300 rpm...never goes below 1000...

anyone got any suggestions? TIA

drjondurst

I had this problem and just fixed it last night actually. It sounds rediculous, but it was just that I had my throttle cable too tight to where it'd always have tension on the butterfly leaving it just a lil open everytime I thought I was idling. I gave it a lil extra slack last night and now my **** is perfect.

mamaboy

I remember an incident with a friend of mine who got an LS/VTEC and due to a vac leak it would idle high. The throttle cable sounds like a good idea...so there's another thing to check...but from first hand observance.....a vac leak will give you an abnormally high idle even when warmed up....check all lines....and I doubt the injectors have anything to do with it....

ludelvr

Okay, well after an hour or so of taking **** apart and cleaning and checking the o rings and stiff like my fast idle valve and iacv and what not, I've finally found the source of my idle bouncing problem. As I was looking for where the hissing was coming from, it was in fact a huge leak that was underneath my fmu. I couldn't see it but after feeling around and ****, I was able to see it. The fmu was butting up against the nipple which caused the nipple to pierce the vaccum line!!

As well, the coolant was a little low so I topped that off, and my engine bay (mostly my intake manifold and throttle body was really dirty because of a crack in my old manifold, I cleaned all that out really well too.

In the end, my idle now sits at around 800 or so (it's hard to tell on my tach, but it's under 1000) and no more bouncing idle. I took it for a rip and I'm still boosting 8-9 psi strong and it feels good. I lift up the hood and there's no more hissing!! Quiet...so quiet and no bouncing!!!! haha. Anyway, hopefully this helps some people out.

Oh yah, and with regards to my air fuel gauge not working properly, the a/f wire that goes to the oxygen sensor reading had disconnected and was grounding itself. I reconnected it and good as new!! No more problems!! Man today is great, all my problems for my car seem to be solved...Knock on wood! Thanks for all the info guys!!

censored

glad everything worked out for you

twkdCD595

check for a sticking pcv valve...

pinch the hose going to the pcv and see if it calms the idle and stops the hiss.