Chopface wrote:
> Hello,
>
> I've got a '91 Civic Si with the stock 1.6L MPFI setup and a manual
> tranny. I put an AEM cold air intake on in August and I don't suspect
> any problems from it directly. It has 136k miles and is well maintained
> as of late (IMHO).
>
> Over the past few days the car has developed an idle problem. I have no
> check engine light indication. The ambient air temp. has been around
> 30-40 deg. F lately. The fast idle seems normal when I start the car,
> but after I have driven the car up to operating temp. (either cruising
> on hwy. or around town) the idle bounces repeatedly from 750 - 1250 rpm
> in neutral with the clutch out. I also seem to be getting lower gas
> mileage (low 30's vs high 30's).
>
> I changed my coolant this summer, and never bled the system. I just
> squished my upper rad. hose a bunch after filling it up and running it.
> I know that the dashpot diaphragm that keeps the throttle plate from
> slamming shut sticks sometimes, but I don't think it would be the source
> of my problems here.
>
> I don't have my Helm manual currently and am going to work on my car
> this holiday weekend. So far here is what I am going to try:
>
> bleed cooling system
> check all vaccum connections
> check for leak around intake manifold and throttle body gaskets
> check EACV
>
> Does anyone have any other ideas?
>
> Thanks for your time,
>
> Mark
>
>

Thanks Jim and Caroline!

Bleeding coolant did the trick. By the way, does the bleed valve leak
air around the threads when you are bleeding? I could always get air to
come out after a bubbleless stream left the valve.

Mark