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Discussion Starter #1
2004 is300

i was away from home for 4 months and only was able to get a friend to warm my car up once or twice while i was gone, when i came back turned the car on and the a/c worked for a bit then stopped cooling altogether, took it to a a/c place where i was told the compressor was bad, and in order to change the compressor "giving the way these cars are made" i MUST change the condenser and a/c expansion valve, and that there is no way around it.

Any of this correct, or could i just change the compressor?
 

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If it was working fine and still is holding pressure in the system. It will be fine to change just the compressor.
 

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Discussion Starter #3
what he is saying is that "the way the system if built in these cars" you cant just change the compressor and drain the system, UNLESS you change the condenser and ac expansion valve aswell

i have never heard of something like this, then again i never had ac issues in a is300, every car i ever owned that had a issue u just fixed that particular issue, i dont understand how the compressor cant just be changed alone and the system recharged, or am i missing something with "these cars"?
 

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Discussion Starter #5
how difficult is changing a compressor? something that can be done? i.e i have changed the sparks plugs and wires on this car, brake calipers, things like that, is the compressor duable?

how can i verify that its actually the compressor thats faulty?
 

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Yes it can be done by a novice. You need tools and some gauges with a vacuum pump. The way you check your system is with gauges. If it is low on 134. You will need to add some to see what is going on.
 

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What he might be trying to tell you (very poorly) is that if the compressor has worn out it may have left debris in the system, if it has the main parts it will potentially clog up and effect will be the expansion valve and the desiccant filter. So potentially you could change the compressor and recharge the system only to find the expansion valve is blocked up or worn out, and need to change that as well. Some AC guys like to back flush the system as well.

Did they actually confirm with the gauges that it is the compressor, not the expansion valve or something else?

Might pay to get a second opinion, could be like my wifes car where the compressor was fine but the expansion valve was jammed.
 

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Discussion Starter #8
i havent gotten around to that yet, i will pick up the car tommorrow, this was all told to me over the phone, which why i want to know to to find out how he came to that conclusion, or how I can find out if the compressor really is the problem. Is there a way to diagnose this?

I know that after changing the compressor (if it resorts to that) i have to recharge the system and all, but can i just change the compressor myself (and im assuming the o rings too) i can just take it to a shop and have them put air in there to check for leaks and then recharge it?
 

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Discussion Starter #9
and i understand what your saying in regards to other parts being faulty, but they are quoting me 1100 dollars, i find that crazy, thats like stealership prices
 

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2002 Lexus IS300
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He is just trying to sell more crap to you to charge you more labor. What I would do is take it to a different ac shop and have them evacuate all that’s in the system and tell them that you are going to change your compressor. Then take the car home and replace the compressor and then take it back to the same shop and have them refill the system. Problem solved.

I just replaced my compressor about 5 months ago. It took me maybe a hour. It was easy. New o-rings will come with the compressor.

This should help:

136497

136498
136499
 
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Discussion Starter #11
thank you

im definitely not afraid to do the job myself, and i see refurb compressors are not that expensive, the only thing is i want to make sure that is whats wrong, i would hate to replace the compressor and then find out that i was the expansion valve.

anyway for me to diagnose this to make sure thats whats the problem?
 

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thank you

im definitely not afraid to do the job myself, and i see refurb compressors are not that expensive, the only thing is i want to make sure that is whats wrong, i would hate to replace the compressor and then find out that i was the expansion valve.

anyway for me to diagnose this to make sure thats whats the problem?
You would need to hook up gauges to see what’s going on. Fortunately for me my friend runs the mechanic shop so I can see what’s going on. The way I see it for you is you can:

1. accept what the mechanic has told you and replace the compressor.

2. pay for another reputable shop to diagnose it.

3. buy gauges and hook them up yourself.
 

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Discussion Starter #13
is there a fuse for the compressor? only asking because im not near the car right now, and right before this all happened while i was away i had somebody else change the battery for me since the one in the car went bad. Last time that happened i had the radio not working and it was a fuse blown not the radio
 

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There is a fuse, but often the relay gives issues so i would start there. Pretty sure you can test by swapping it with one of the fan relays.

Over here gassing and degassing R134 is fairly expensive (I think it cost me about US$150 equivelent) so the last thing i want to do is crack the system open unless i know fairly sure what is wrong. If it were me and the relay or fuse doesnt work I would take it to another shop and ask them to put the gauge set on it to check the hot and cold side pressures. If it is the right pressures on the hot and cold sides from memory that means the compressor is working and there is enough gas in the system (someone correct me if i am wrong), so its potentially something else. On the wife's car the pump was staying on continuously which indicated the expansion valve wasn't switching over so the shop said, i googled and confirmed before ordering the replacement and swapping it out myself. Just depends on what the exact symptoms are for your issue.
 

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There is a fuse, but often the relay gives issues so i would start there. Pretty sure you can test by swapping it with one of the fan relays.

Over here gassing and degassing R134 is fairly expensive (I think it cost me about US$150 equivelent) so the last thing i want to do is crack the system open unless i know fairly sure what is wrong. If it were me and the relay or fuse doesnt work I would take it to another shop and ask them to put the gauge set on it to check the hot and cold side pressures. If it is the right pressures on the hot and cold sides from memory that means the compressor is working and there is enough gas in the system (someone correct me if i am wrong), so its potentially something else. On the wife's car the pump was staying on continuously which indicated the expansion valve wasn't switching over so the shop said, i googled and confirmed before ordering the replacement and swapping it out myself. Just depends on what the exact symptoms are for your issue.
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what he is saying is that "the way the system if built in these cars" you cant just change the compressor and drain the system, UNLESS you change the condenser and ac expansion valve aswell

i have never heard of something like this, then again i never had ac issues in a is300, every car i ever owned that had a issue u just fixed that particular issue, i dont understand how the compressor cant just be changed alone and the system recharged, or am i missing something with "these cars"?
As an HVAC student, my professional opinion is to replace it all, condensor, evaporator, compressor, and the Expansion valve or Metering device, havent gotten a chance to take a look on these cars. After all, something in the system made the compressor go bad.
 

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Discussion Starter #17
maybe it wasent something in the system so much as the car was sitting for 5 months without being started, also i do not have the money to just replace the whole ac system

anybody know which is the relay for the compressor? the diagram on the back of the black box lid dosent specify
 

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Discussion Starter #19
thank you

i went to another shop that did free a/c test, they told me that there is no freon in the system and they need to put in some dye to find the leak to then find out what was the problem, i eventually told them i think its the compressor and they immideatly told me the same crap, that i have to replace everything, but if i want them to just replace the compressor its fine with them but they dont give no guarantees if i do so, the guy went on to tell me that the condenser of these cars are "sealed" and replacing just the compressor WONT WORK

i have a can of freon and the hose to put it in, im thinking of putting that can in to atleast see if the compressor engages, im thinking that if the system cools with that can for a while then maybe its just a leak and the compressor is ok???
 

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I've been hesitating to say anything. But all of these people are right. I did what you are trying to do, replace one thing at a time. Eventually, I gave up. When the compressor goes back, it will still "engage", but nothing will happen. When it goes bad, it sends junk into the system, which always clogs up the expansion valve and potentially the condenser. Opening the system at all to the air requires a new drier. And the problem is that you can't just test it easily, you have to get a full vacuum and fill every time you mess with it, and then a professional drain to open it back up. So in the end, it's always best to just do it all at once. New compressor, new expansion valve, new condenser, new drier. Then make sure it's all sealed up, and put in the freon with dye after a good vacuum.
 
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