2005 Tacoma 2.7L A/C problems

Hi,
I have a 2005 Toyta Tacoma Access cab 2.7L and the A/C is giving me some problems. When we first bought the truck the A/C compressor went out after a year. So we bought a new compressor and put freon in it and it worked for about 2 summers and this summer it didn't blow cold. So we figure there must be a small leak in the A/C system. I go with my dad to his work and we first vacumed the freon for 20 minutes and the machine only picked up about 0.2lbs of coolant. I didn't know how much to put in the truck and we couldn't find the sticker which says how much to put in so I went online on my phone and found out that it should be about 1.4 lbs but that seemed kind of low and we put in 1.7lbs. I called a local dealership today and they said it should take around 2lbs. The A/C does not get cold until I drive the truck on the freeway but even then it doesn't get as cold as it used to be. I also hear a little ticking sound and my dad said its probably coming from the A/C compressor clutch. What else could be wrong besides the leak?
Thanks,
Matthew

 

if the original compressor grenaded, it could have contaminated the system. have you checked hi/low pressure/temperature? that could show you a blockage (likely at the dryer or txv) but I think it would be hard to diagnose a blockage unless you are sure on the correct charge amount.

I do not know a ton about auto a/c or any a/c for that matter. but if your dad has access to a vacuum pump, he or somebody close to him should be pretty knowledgable.

as for leaks, did you test to see if it held vacuum? how many microns did you suck it down to? if it leaks, I highly suggest pumping up with nitrogen as its much easier to find a positive pressure leak

 

Hi Kevin, thanks for the help. I believe the pressures were fine but I'm not sure about the temperature. I think the A/C system is contaminated because of the old compressor like you said. It held vacuum fine. Maybe its the A/C expansion value or the desiccant element.

 

Okay so I went to our local dealership today and they said that the receiver/drier is built into the condenser. We looked at the condenser today and it appears to be sealed shut. There is an metal ring that closes the left side and I believe the receiver drier is underneath it. Does anyone know if it is replaceable? If not should we just buy the entire condenser? This is what the condenser looks like

$98 RAREELECTRICAL NEW AC CONDENSER COMPATIBLE WITH TOYOTA 05-13 TACOMA TO3030205 10441 P40426 3017 8846004210 P40426 10441 TO3030205 3017 7-3393 8846004210

http://www.amazon.com/CONDENSER-TOY...50277&sr=1-8&keywords=condenser+toyota+tacoma
Thanks,
Matthew

 

Notes for the future: Always replace the Dryer when the compressor grenades. Always!

This is the reason. Your compressor may also be dying a slow death from the contamination.

 

matt3D, sorry to hear about your A/C problems. Let me see if I can help you out some.

The receiver/drier is built in to the condenser and can not be serviced. Unfortunately, the entire condenser must be replaced and the OEM is some gastly amount. Fortunately some of the aftermarket are pretty good and even have a decent fit and may be a more affordable option.

I'm concerned about the first compressor failure. If that compressor shred debris throughout the system what is happening is the debris is finding its way back to the new compressor and ruining it as well. It will also ruin the next compressor and so on. Do you know if the original compressor "grenaded"?

Your truck must be charged by weight and weight only. This is so important that I am going to underscore this and repeat it. Your truck must be charged by weight only. Your truck's fill volume is 22.1 to 22.2 oz., no more no less. R134a systems are very picky about how much refrigerant they take and Tacoma's like to be right on. A little too much or to little will produce the same results: poor cooling. Worse, R134a systems run at high pressures and overcharging with either refrigerant and/or oil will likely blow hoses and other components.

The little 12 oz. cans are a bad way to charge IMHO because getting the correct amount in is difficult. The problem lies with estimating how much has been used, losses in the hoses and cans, and the introduction of air into the system from hoses which have not been purged since air does not cool but still compresses and raises the system pressures.

A system that has been open begins to take on moisture immediately and the longer it is open the more it acquires. Typically a deep vacuum will be necessary to remove most moisture as any left in the system likes to freeze up in the thermal expansion valve (TXV) and in the evaporator. The result is no cooling or erratic cooling until the ice thaws.

The best way to draw a vacuum is with a good vacuum pump, clean oil and measuring using micron gauge. Sometimes as little as 1/2 hour is needed but sometimes it is very difficult to break away those particularly pesky water molecules hanging in corners and on other surfaces and it may take much longer.

Did you keep records of how much oil might be in the system? New OEM and the Denso compressors come with 150cc (5.1 oz.) of oil and you are supposed to measure how much was in the old compressor and take out oil from the new compressor to match what was in the old. Besides raising the system pressures too high excess oil takes up space that could be had for refrigerant.

A/C work is one of the few things that I recommend the pros do. Most people simply do not have the necessary tools or skill to diagnose or service the modern systems because they are less forgiving than on older cars.