Also having idle problems

[hsilman]

Hey guys, just need a little help. I'll give a bit of background info, then get to my current problem:

 

I just bought a 91 'Lude B21A1, very nice and all. I was having trouble with it because I would start the engine right up and it would be fine, then after a few minutes of running it would start dropping RPM and then bounce back up again. I managed to "fix" that by putting my hand over an opening that sucks in air.I don't know what the part is called, but the throttle is attatched to the front of it, and it sucks in more air when you rev the engine.

 

Anyways, I lightly held my hand over the intake, and eventually it evened out the idling. So I thought "hey I fixed it, cool." So I walk away and left it running for a bit, because the battery had died(for an unknown reason) and I needed to let it recharge after the jump. So I came back down about 30 minutes later and my car had shut off. And now here's the current problem:

 

When I turn the engine on, it idles incredibly low(under 500) and eventually(after about 10 seconds) just sputters and dies. When I try to rev the engine in neutral(it's a standard, fyi) it doesn't do anything for a second, then slowly chugs it's way upwards, with a literal sound of "chug chug chug" then it eventually "catches" and revs up with a normal sound. But when I let off the gas, it just drops right back down and dies. Putting it in gear is impossible, it just dies when I try and let off the clutch.

 

Any suggestions would be incredibly helpful. As to what could be causing the battery to just drain and die, well I think it could be too many things so I'll just bring it to a mechanic and maybe they can figure it out.

 

Thanks a lot!

[hsilman]

OK update time!

 

I just started the Lude up again today, and the problem changed back. Now after about a minute of idling, it starts dropping to 1500rpm and reving back up to 2000. back and forth, back and forth. Not always those exact RPMs, but around there.

 

Any suggestions?

 

Edit: After a few minutes it starts jumping between 1200 and 1500 RPM

[SexyH22]

could be alot of things. idle air control valve (iacv), fast idle valve, or an air pocket in your coolant lines. try beleeding your coolant first, since its free, and check your res.

 

 

i think its prolly your iacv.

[hsilman]

check your res.

 

Sorry if this is a dumb question, but I'm new to working on cars and stuff. What do you mean by this?

 

Also, do you possibly have a link, or could you tell me how to go about bleeding the cooling system? The Chilton's guide I have only shows where the bleed bolt is on an Accord, not the Prelude.

 

Thanks for your help

[SexyH22]

chck the reservoir for coolant to see what the level looks like.

 

there should be a small bolt w/ a nipple coming out of it near the thermostat housing, if you let the car run, and open the valve by loosening the bolt then it shoould bleed it, just let it run until some coolant starts to come out of it.

 

 

atleast thats how i ddi ti on my delsol, never had to bleed the coolant in my prelude.

[Timmythewop89]

you said your battery was dying. check your alternator. if its not charging your battery correctly, the computers that run your motor at specs dont function properly. an alternator crap the bed on one of our yukons and it had very alike symptoms.

[hsilman]

would an IACV from a 1989 b20(2.0), 5-speed engine work with my 1991 B2a1 5-speed?

[SexyH22]

i have no idea.