E81 idle speed issue

[spazomatic]

my 84 is all stock (carb rebuilt by me maybe 5,000 miles ago), with 220k-ish miles. it runs real well, but the other day, out of the blue, I come to a stop and the idle is really really low. like maybe just 200rpm. it stayed running kindof, but it sounded a bit rough as well.

if I give it just a little gas, the idle comes up and smooths out.

 

the next day I plan on working on it, but she fires right up, idles perfect, and I couldn't get it to do it again. I write it off as a fluke and forget about it.

then I go to drive it to work, and it starts idling goofy again!

 

it acts like a carb problem, but I figure it's an emissions doodad causing the problem.

please enlighten me subaru gurus!

[hatchsub]

Do you still have your EGR valve? Im wondering if that is getting stuck open sometimes and not others.

[spazomatic]

it does still have EGR. all the emissions are intact, except for the lines that add air to the exhaust (can't remember what it's called...too early, need coffee:slobber:)

I'll check that again. I did plug the line to it, and it didn't seem to make a difference

[TeamCF]

I've had mine do that from time to time on me. Same deal, it can be fine all day, then it'll just decide to almost die when I idle at lights. Then it runs right either later or the next time I start it up.

 

All my emissions stuff is gone except for the EGR and CAT. Pretty much as per GD's "Living with your Hitachi" threads. (and when I did my engine swap I couldn't get the air pipes from under the heads undone, so I plugged them on the new engine, really cleaned things up under there and still does the DEQ just fine, cost me $0.50 .... )

 

Anyway. Mine's an 83 GL with a recently rebuilt "Craptachi" (but I find it works just fine except for this) as a reference.

 

So far I've just used it as a hint to clean the carb and do some adjustments. Seems to keep the episodes of low idle stalling far apart. Some Seafoam, spray carb cleaner, flat blade screwdriver, and 15 minutes makes it go away for months at a time.

 

The previous owner drilled out the plug on the idle mix screw on mine. Oddly enough while it's running I'll run the screw in and out a few times (keeping track of turns so it goes back to where it was, but I know the adjustment just in case) and it makes it run better.

 

So I'm betting a bit of crud gets lodged at the screw point, and chokes it a bit until it washes out of there...... But that's just what I'm thinking it is on mine. Yours could be a different problem altogether (and so could mine for that matter) and I'm just rambling on now.

Edited August 27, 2010 by TeamCF