A/C Problems.....

2000 Blazer 4 door 4x4 LS


The A/C never rain cold and am trying to find out the cause.


The clutch on the compressor is scraping against the pulley. (which may cause it to not engage (i Think) )


Then i think that the evaporation tube that leads to the underbody of the truck may also be clogged causing the moisture to develop a large amount of water under the carpet.which could cause potential damage.

Any other ideas on how to repair or anyother suggestive things that could cause would greatly help.

With the engine at approximately 1500 RPM and the AC switch on the dash in the MAX AC position:

Does the compressor clutch engage?
Does the compressor cycle on and off?
Does the accumulator get cold? (large aluminum "can" next to the evaporator housing)

If the evaporator drain is clogged, it will cause condensation to leak onto the passenger side carpet. It can also cause the evaporator to "ice up" and become a block of ice sitting inside your dash! If/when that happens: initially the air flow through the registers will be normal and cold. As the evaporator ices up, the temperature will gradually get warmer, and there will be noticeably less air flow through the registers. When you shut the AC off, the ice block melts and makes a mess on the floor. The drain hose is "neatly tucked out of the way" on the underside of the evaporator housing accessable from under the vehicle, within a couple inches of the firewall, (very difficult to see, and even more difficult to get to).

With the engine at 1500 RPM's the clutch on the compressor stays stationary as the pulley continues to rotate.

Like what you told me the evaprator can does get cold and from what you described it is what happens in mine except the water is on the driver side not the passenger side.

Automatic Climate Control or Manual A/C?

It is a manual A/C system,

I also noticed that the heat in not working as it should, could they be interconnected.

Have you checked both sides of all fuses in the dash fuse panel and the under hood fuse panel? When the engine is running and the AC switch in the "MAX" position, is there battery voltage on one of the wires at the switch on the accumulator?

I looked at a total of 5 fuses that were hvac and ac related and were all in working condition.

When the engine is running and the AC switch in the "MAX" position, is there battery voltage on one of the wires at the switch on the accumulator?

i disconnected the connection here and tested it with the volt meter, ( if this is not where you meant ill try there later) but when i put the reader into the connection on the cable it cause my compressor clutch to engage.

I dont know what this means.

It appears there is voltage at the connector ;) That is the correct switch. It is the clutch cycling switch. It engages the compressor when accumulator pressure is above 42psi, and disengages it when pressure drops to 22psi. Either the switch is faulty, or system pressure is below 22psi. If pressure is in fact low, the system probably has a refrigerant leak and needs to repaired. Then the system will need to be evacuated and recharged.

COuld it just be due to the fact that the freon was never charged

Yes, when you connect the manifold gauge set, if high and low side both read less than 22psi, it's either low or empty.

Thanks so much i'm gonna go get that done.

I now noticed that my heat is not working anymore.
It worked this previous winter.

Any ideas.

Does the temperature gauge on the dash show approximately 200 degrees after driving for 15 minutes?

After the 15 minute drive, are both heater hoses hot and approximately the same temperature where they connect at the firewall?

The hose on the left side is hotter than the one on the right.

Remove both heater hoses where they connect to the engine. Point one hose to the ground and connect a garden hose to the other heater hose. Turn the water on and flush until the water comes out clear. Then connect the garden hose to the other hose and flush again in the opposite direction, until it comes out clear. Reconnect both hoses, fil with coolant and check the temp of both hoses again. Post your results.

Remove both heater hoses where they connect to the engine. Point one hose to the ground and connect a garden hose to the other heater hose. Turn the water on and flush until the water comes out clear. Then connect the garden hose to the other hose and flush again in the opposite direction, until it comes out clear. Reconnect both hoses, fil with coolant and check the temp of both hoses again. Post your results.

Old master,

You don't want to put a lot of pressure into the hose from the garden hose, Right? Possibles damage the HC from too much pressure? Just flow it down the heater hose not conncect the two to create higher pressures. I know household pressures can be 100psi but most will be around 50.

Correct, let the water free flow through the core and hoses. Don't plug off the end of the heater hose, that way, pressure can't build up. If it does, the core is restricted and needs to be replaced anyway.

I flushed it out till it became clear, was it suppose to be gushing out or trickling out because the one side just trickled out mostly.

Where was i suppose to add the coolant to, the actual tube or the reservoir?

I went for a drive, i had some heat but it dissipated soon after.

Water should gush out with little or no resistance in both directions when flushing. If it does not gush out, the core is restricted and will need to be replaced.

New coolant should first be added to the radiator, then run the engine at operating temp adding coolant as the level goes down until it's full. Add coolant to the reservoir as necessary to bring it to the MAX line.

I re-flushed the heater core with water first then with some light duty drain clearer. significant blockage was visible.

Started the car and drove and had continuous heat.

If the core was that bad, you might want to think about a professional power flush and then refill with Dexcool coolant. DO NOT use the green ethelene glycol.