Hello Austin..you have helped me in the past with an automotive problem..hope you can help again. Here is all the info I know it’s hard w/o looking at car, but please respond..thanks:

Air Conditioning problem
1998 Kia Sportage 4 cyl Two Wheel Drive Automatic

lOW SIDE =40 PSI
HIGH SIDE=240 PSI
outside temp (FLORIDA)=92 degrees (F)
topped freon off since it was not blowing cold at all; pressures read as above with blower on HIGH.

THE low side ac pipe coming out of engine firewall(evaporator) is warm, other high side pie (ac line ) is HOT to touch. What could be wrong..BOTH fans come on (ac condenser and radiator fan..car NOt overheating)..
problem seems intermittent. Sometimes car will blow cold air (only when pipe coming out of evaporator(low side is cool to touch and sweating; otherwise, pipe gets hot again and will not cool car.

Both fans(AC CONDENSER and radiator fan turn on). Car not overheating..PLEASE advise,
Thanks
Gail

Hey there Gail

Your numbers are not that far off. First I would hook up your gauges again and rev the engine RPM to 1500, and see if those numbers change. I would expect them to be about 20-30 low side and 250 – 280 or so on high side during the heat of the day on high blower at fast idle. I am thinking you just need to add a little more Freon to the system at fast idle. Sometime you have to use a stick on the accelerator cable under the hood as you add more Freon.

I have also seen similar numbers and complaint when there is a contaminate in the system, like AIR from a recent part replacement or too much compressor oil that was added to the system. if adding more Freon does not help the problem I would suck out the system and evacuate for about an hour then refill the system.

Blessings
Austin Davis

Hi Austin

Thanks for your help…we did put freon in at 1500 rpm..the low side ac pipe coming out of the firewall(evaporator) gets warm to touch intermittently..when it does, no cold air blows..but when it sweats and is cold to touch, it blows cold a/c. The other ac pipe is hot to touch coming out of evaporator.

Someone else told me the pressure numbers were correct but that the BLAND might be stuck near heater core??..it seems to run cold for awhile, then all of a sudden won’t blow cold anymore.

I will have someone evacuate and recharge.
I did not add any sealer or oil..just freon..about a half a can and then we stopped because the HIGH side pressure kept creeping upwards. Low side seemed fine at 40psi
what is a bland door?
thanks

GH

Hello again

They are referring to the BLEND door inside the heater/evaporator case which moves when you select HOT or COLD air, it diverts air from the hot heater core or the cold evaporator core.

You can bypass the blend door as a culprit by crimping off both heater hoses going to and away from the heater core so NO hot coolant gets inside the evaporator case. This will NOT cause the car to overheat etc etc it will just not allow hot coolant inside the dash of the vehicle.

Blessings,
Austin Davis

Dear Arnold,

This unfortunately can happen more than you or I want it to. A certain amount of high-pitched brake noise is considered “normal” these days because of the harder semi-metallic disc brake pads that are used on cars now. In my experience, the smaller cars like Honda and Toyota seem to have the most trouble with this. Squeals heard the first few stops in the morning when the brakes are cold and somewhat damp from dew, and squeals that are heard the last few feet while coming to a stop are usually nothing to worry about.

Semi-metallic brakes are made of bits of metal shavings in place of the asbestos material that has been banned by the U.S. government. These semi-metallic brakes have great stopping power and have a long wear life, but can cause a high-pitched squeal that drives car owners crazy and frustrates mechanics who can’t get it to go away to please their customers.

When are squeals not a problem?
Some brands of semi-metallic pads are inherently noisier than others because of the ingredients used in the manufacture of the friction material. Think of it this way, the longer life pads or pads that claim to have more stopping power usually contain more metallic material. Yes, they will last longer and could enhance braking but the chance of causing a squeal noise is very high. The squealing noise that might be caused from use of these pads does not affect braking performance and does not indicate a brake problem.

Brake squeal is caused by vibration between the brake pads, rotors, and brake calipers. Having the brake rotors refinished or trued (machining a small layer of the metal away from the disc brake rotor to make it smooth and “true” again) and a thin layer of a silicone compound placed on the back of the brake pads are a great way to reduce the squeal if the semi-metalic pads are the culprit of the noise and not due to a worn out disc brake pad.

Why does this squeal happen anyway?

The brake rotor is the round metal object that the brake pads squeeze together like the white part of an Oreo cookie. The rotor is metal and has a smooth slick finish, and the brake pads are made of metal shavings and also have a smooth somewhat slick finish. The more metallic material found in the pad the greater the chance for noise, and vise-versa.

The other type of brake pad is called organic. There is no metallic material used in this kind of brake pad. Organic style brake pads can only be used on vehicles that are specifically designed to use them. Improper use of organic pads on a vehicle designed to use semi-metallic can severely reduce stopping ability. Organic pads are softer than semi metallic and usually do not have a squeal problem. Unfortunately due to shorter life expectancy, inability to stop larger vehicles, and the addition of substances like asbestos in their construction, they are not very widely used.

When are squeals signaling a problem?
Sometimes brake squeals are an indication that maintenance is required. Some common conditions that cause brake noise are:

1. Heat cracked or worn “un-true” rotors

2. Rough finish on resurfaced rotors

3. Loose fitting brake pads in the brake calipers

4. Lack of silicone compound on back of brake pad

5. Missing springs or anti-rattle clips that should be on the caliper or pad

6. Improper tightening sequence of lug nuts or caliper hardware

7. Contamination on the brake pad i.e. brake fluid or grease

Most GM cars are equipped with a small thin piece of metal attached to the brake pad to act as a warning indicator when the pad material is getting low and the brake pads should be replaced. This inexpensive warning device can be deceiving though, because this warning noise is present when the brakes are not depressed. When the brakes are applied, the warning noise goes away because the indicator has now been forced against the brake rotor and is not able to vibrate which causes this whistling noise.

If you hear brake noises other than a squeal, it could mean your brake pads are worn out and need to be replaced. If your brake pedal feels different than normal or if you’ve noticed any change in the way your vehicle brakes (pulls to one side when braking or requires more pressure on the brake pedal), or loss of brake fluid have the brake system inspected at once.

What should I do?
What can you do as a customer to reduce the chance of squealing brakes? First of all, noisy brakes should always be inspected to make sure there isn’t a problem with the braking system. If the pads have worn down to the point where metal-to-metal contact is occurring, your vehicle may not be able to stop safely, and you may damage the brake rotors or drums to the point where they have to be replaced. Sometimes a few harder-than-normal stops can “de-glaze” the brake pads and help reduce the squealing noise for a while.

There are many aftermarket brake pads that claim to be “quiet” or have been “designed” for import and front wheel drive vehicles that you can choose from. Personally, I have had the best luck replacing the disc brakes on small vehicles like Honda and Toyota with original equipment pads from the dealership rather than using aftermarket brands. It is usually more expensive to purchase these pads from the dealership, but the quality is much better. I am an independent shop owner and my whole business philosophy is to buy as little as possible from dealerships, but after trying many squealing aftermarket brake pads, I have learned my lesson and pay the extra money.