A.C.

Tenured Impala owners owe a debt of thanks to the N.A.I.S.S.O. posts. So many times problems were resolved almost as soon as they cropped up. Impala owners were armed with the knowledge of many!  In the early years members posted at a furious pace. In this example the following question was posed

I have recently noticed that while driving and operating my AC and coming to

a stop that the AC compressor seems to stop running as the cold air coming

from my vents suddenly becomes warm. Upon returning to normal driving

speed, whether driving at say 25 mph or 50 mph the air coming from the vents

changes to a nice ice cold temperature. What might be the problem and where

do I start checking. Thanks in advance.

Wasn't long and Ken Guzzetta posted a great reply:

So many of us have experianced this event - and can validate his words. Next up is a nice step-by-step coolant flush.

Subject: Heater Core Fix

From: "Joe Nash" <jnassh@earthlink.net>

Date: Wed, 10 Oct 2001 19:13:30 -0500

X-Message-Number: 8

Ryan and List,

I was wondering when this question was going to pop up! Now that the cool

weather is here. The best fix is to flush your system totally, there is so

much gunk in our cars cooling system, that i plugs the heater core inlet

hose at the Restrictor. The Restrictor is in place so as to protect the

heater core from increased pressures during WOT. For a easier quick fix

follow my tried and true directions:

Starting with a cold engine, place a suitable catch pan under the water

pump. First locate the heater core inlet and outlet hoses. You will see

that the water pump has two approximately 3/4" inside diameter hoses coming

from it on the left side of the pump. The top hose is the outlet, and the

bottom is the inlet. You will have to obtain 2 rubber or cork corks that

would fit inside a 1/2" to 3/4" pipe. Remove the top hose and quickly

insert the cork into the pipe coming out of the waterpump while directing

the hose downward into the catch basin. Now after the top hose drains, move

to the bottom hose. This hose will be the gusher. You must be quick here,

other wise the coolant from the block will come rushing out. Slowly remove

the hose, and quickly put the cork into the pipe coming from the waterpump

while directing the hose into the catch basin. This will completely drain

your coolant tank. Ok...

After the hoses are done draining, Locate the tee by the coolant recover

tank. You will see it just to the right of the tank. Disconnect the hose

from the back of that tee. Ok this is the back flushing part. You may want

to catch this stuff in a separate container to see how much crap you got

out. With your mouth ( the heater core will not tolerate high pressures)

blow on the hose you just disconnected from the tee. You may have to blow a

few times to clear the remaining fluid out of the heater core. Now look at

the fluid you caught. You will be amazed at the clay like sludge that

appears. Now what I do is, take a garden hose and run a low pressure stream

of water into the hose, and watch the flow until it turns clear. You may

want to repeat the blowing procedure again to make sure all the gunk is

removed. Then run water again until it runs clear. After that, button it

all back up, remember though you have to be quick when you reconnect the

bottom hose as alot of coolant will coming out of the waterpump when you

pull the cork loose. Then fill the coolant tank back up, then start the car

and check for leaks. Also while the car is running, check out the nice heat

you get now. Check again after the car cools down to see if you have to add

more coolant or not. then you will be done.

The Air Conditioning System in our cars is fairly dependable - but not quite glitch free. Here we see what is likely the most common hot weather failure.