Contour Enthusiasts Group Archives Forums Modifications Zetec Maintenance AC noise?

Zetec-VCT 2.0 L4 1998

Okay.. When I'm in Park everything is fine.. Sometimes I do here a noise like a vacume leek and there is an engine code. However this might be another problem not related to the AC noise.

When I put the car into Reverse or Drive the RMPS's drop.
When I turn on the AC the RPM's drop.
When I use the brake the RPM's drop.
When I turn really Sharp the RPM's drop.

All of these things I feel are normal and the car should see
these adds and adjust to them. However the car takes its
sweet time before doing so. There is a 3 second gap when
adjusting that allows for the car's RPM's to sway from 750
down to 500, but after 3 seconds it revs back up to 750.

Sometimes at a red light the RPM's will just drop down for
no reason, runs ruff and then pic's back up.

When the AC is running there is a chirping sound. This the
Serp built is loose. I don't see or feel any slack but I
can see the engine vibrating more than I would like. This
noise does not normally happen until im at a stop light.

The car has no problems at high speeds. No noises and zooms..

It's driving me crazy.. when I stop at a light and the AC is on I keep thinking, "This is a 98 car WTF?"

I feel it's more in combo when the Brake booster and AC unit are booth working. Hmmmm...

Lol.. no reply.

I guess I'm just asking the wrong questions?

I wish I could add something positive to this but alsa I cannot. I would liek to let you know that you are not alone in this as my Contour demonstrates some of the same behaviors.

Same here

He chirping is just or AC clutch, they will do that when they get old. The drop in RPM is normal as long as the car stays running. Clean/replace the IAC if it seems like the engine is too slow to respond to changes in load.

jeff

May I inquire as to what IAC means and does this site have a dictionary? TIA

Being a techie-type site it's called Terminology , part of the informative FAQ section on home page.

When one's foot is off accelerator throttle cuts off intake air to engine. IAC valve bypasses throttle and provides sufficient air to maintain idle. Valve receives varying signal from PCM, to try and maintain spec idle rpms, depending on various engine sensor inputs.

I jacked her up today. Was looking for the IAC.
I was looking up at the part and trying to figure
out how in the heck do I get this part off? There
is just too many things in the way and this might
be really hard without any air tools.. Will need
to wait until saturday when she is cold.

So anyway.. There is this rubber hose in my way.
This does not look to be in good shape. I'm still
not sure what hose I'm looking at. I can't see where
this sucker goes around to the top. It looks sort of
like the breather hose. It comes out in the middle of
a 3" thick black pipe that runs along the firewall.

I do recall seing some black carbon when I was cleaning out
the throttle body in a small hole at the very top. Maybe
this is where the part goes?