Idling prob, part 2ish

[Spazz698]

ok after I replaced the alt. my idle went weird, I went to class and had my teacher help troubleshoot what was going on and we cleaned out the tb, checked for vacuum leaks, cleaned the IAC valve and readjusted the throttle as low as it would go (initally this was 1k rpms) Drove it home, the idle dropped to about 700-800, which was roughly the place it was beforehand. The idle was steady, everything was fine. Now the car's slowly starting to do it again, just in smaller steps than last time (ie Im driving down the hiwy going 80 before it was worked on, let off the gas and the rpms would go from 3k to 2500, jump back up to 2800, drop again, now instead of that big jump it'll go from 3k to 2800 or so) when it's at a stop idling it'll go anywhere from 5-800, me just watching the needle bounce. when me and my teacher worked on it he pinched the small idling hose to the tb and the rpms should have dropped if not died and nothing. It stayed idling at 1k like it was the entire time. I'm not sure if he checked to see if there was a vacuum coming from there (I can check that real quick) but neither of us can figure out wtf is going on. I'm gonna pull my car back into the shop and mess around with it tomorrow, but if I need parts I'd rather get them before class

 

sorry if I made a few mistakes there, Im tired and my brain is offically fried for the night, I spaced on a couple things for sure!

[beezer]

Not sure if I read part 1 of your saga or not, so I don't know what suggestions have been made.

 

If this problem started after replacing the alt., then I might start there. Take the alternator and battery in to get tested. Quite possible you got a bum replacement.

 

When you said you pinched the small hose going into the TB you're talking about the one going into the IAC right?

 

If the car can still idle with this hose completely pinched, then it would be fair to say it is getting air from somewhere else. If you have checked for vacuum leaks and there are none, then maybe the throttle is stuck open. Check the cables that connect the throttle, there should be some slack at idle. Could it be possible the butterfly thing inside the TB isn't closing?

 

I would check the knock sensor too, hesitation around 2500-3000 rpm is quite similiar to what I have experienced with my car.

 

Not sure if this is any help or not. Good luck!

[Spazz698]

I had the electrical system checked out, no probs there. Im being told theres a small chance I "mightve hit something" when I replaced the alt but come on...how the hell would that happen considering the placement of the alt? No way! lol 2 brackets and a belt (and some wires) and its out, on many other cars yes but not this one.

 

oh hey now that I think of it, I wonder if my tb is doing something similar to my bf's old prelude- the butterfly clip on the inside kept unscrewing itself out of place causing an annoying sounding irratic idle (at one point the car wouldnt run for $#!^ cuz the screw flung itself elsewhere) that never even came to my mind....

and yes the hose connected to the IAC, kinda started spacing when I wrote this (been up way way too long) if all else fails Im gonna just start plugging stuff til it chokes tomorrow when I get the chance.

thanks beezer, Ill let you know if I break it lol