i work at a quick lube and have access to an a/c charge machine so i hooked up my 95 lude vtec... i charged it once already with no results like a week ago. so today i vaccumed the system for 18 minutes and then charged it back up with 22 ounces but it still blows hot! i checked my hot/cold adjuster cable and it seems to be working fine and you hear the click when you turn the a/c button. it looks like the compressor is running fine it engages but i just can't get it to work. so i tried one troubleshooting technique, i started the car to see the pressure of the high and low sides...the low was jumping up to like 80 and the high was staying at like 7 which according to the a/c manual means the compressor is bad. what do ya think? is it a big job changing a compressor?

 

expansion valve is not opening, or it might be clogged up

 

yea, I was gonna say expansion valve too...

 

I'm taking my workin compressor off tomorrow if you're interested in it.

Can't wait to take all the ac stuff out......its gonna be great.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PrettyLude &raquo;</TD></TR><TR><TD CLASS="quote">expansion valve is not opening, or it might be clogged up</TD></TR></TABLE>

I think I have the same problem. I replaced a bad compressor (it was definitely bad) but the AC still does not work. A guy who checked it said the compressor was working, but something else is causing the problem.

How hard is it to change the expansion valve? Can I do it myself?

 

Just so that you are fixing the right problem, does your climate control A/C button light come on when you push it? If it doesn't, then your climate control board needs resoldered. It take a couple hours (mainly opening up the dash), but is a fairly easy fix. 4th gens just have this problem for some reason.

I thought my compressor was bad too. Resoldered the board - voila - cold air bliss.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Lewdin’ Incognito &raquo;</TD></TR><TR><TD CLASS="quote">Just so that you are fixing the right problem, does your climate control A/C button light come on when you push it? If it doesn't, then your climate control board needs resoldered. It take a couple hours (mainly opening up the dash), but is a fairly easy fix. 4th gens just have this problem for some reason.

I thought my compressor was bad too. Resoldered the board - voila - cold air bliss.</TD></TR></TABLE>

That was the first thing I fixed before getting the compressor. I made sure that wasn't the problem.

The guy who looked at my AC system said it was holding pressure. He said that the pressure seemed to keep building up in fact. He said he thought there was a clog somewhere. I had no idea where to proceed from there.

If I can't get it fixed, I plan to pull the whole AC system. I don't want to but I don't want to have to pay a lot of money to fix/replace the system either. My SMSP header is starting to melt my AC hose too. Getting the AC to work would be great, but not dire since it's not my daily driver. However, my goal for the car was to get everything working on it.

 

you can replace the expansion valve. They are sort of pricey though. They are located under the dash under the glove box. When i tried to charge my system when i first got my old lude, it got cold for a minute and then the a/c compressor started to smoke!! And the pully burned up. My expansion valve was stuck and the pressure on the lines burned it up. So I am not sure if the expansion valve is what is bad. Because if it is stuck..then it is going to build a ton of pressure up and possibly burn out the compressor like mine did.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdmlude_dude &raquo;</TD></TR><TR><TD CLASS="quote">you can replace the expansion valve. They are sort of pricey though. They are located under the dash under the glove box. When i tried to charge my system when i first got my old lude, it got cold for a minute and then the a/c compressor started to smoke!! And the pully burned up. My expansion valve was stuck and the pressure on the lines burned it up. So I am not sure if the expansion valve is what is bad. Because if it is stuck..then it is going to build a ton of pressure up and possibly burn out the compressor like mine did. </TD></TR></TABLE>

That's what the guy told me. The pressure kept building up but the air never got cold. I would assume it is the expansion valve since you are saying yours did the same thing.

Did you change the valve yourself? If so, how hard? How much was a new expansion valve?

EDIT: Ahhh, found it. It's $66.

http://www.hondaautomotivepart...81%29

 

i never changed it.. i just took it all out. from what i know...it isnt that hard though. if you want air i would say it would take about 30 mins or so.

 

its not that hard to change, the valve itself from the dealer is around 60 bucks. if the pressure keeps rising like you are saying the expansion valve has to be clogged, causing the high side to peg out. either that or the dryer is clogged, but im willing to bet that the expansion valve is the problem. pm me if you have anymore questions.

 

i guess i will order up an expansion valve and reciever dryer tomorrow. i'll let you guys know asap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PrettyLude &raquo;</TD></TR><TR><TD CLASS="quote">its not that hard to change, the valve itself from the dealer is around 60 bucks. if the pressure keeps rising like you are saying the expansion valve has to be clogged, causing the high side to peg out. either that or the dryer is clogged, but im willing to bet that the expansion valve is the problem. pm me if you have anymore questions.</TD></TR></TABLE>

Wow, thanks for the help.

If I change it, will I have to empty the freon and then re-fill it or can you change it without affecting the AC freon?

I figure I will tr this fix. If it works, great. If not, I'll just pull the whole system.

If anyone has a write-up on how to change the valve, please post it it!!

Thanks!!

 

andy d to change the valve, just get ready to pull the evaporator out, cause its right in front of the evaporator, and it wouold be great if you have an a/c machine, because it will require you to discharge all the freon out of the system. but for every a/c system to work at its best, the system must be vacuumed really good before freon goes back in. "ideally" once you open the system up like you are doing you are supposed to replace the dryer, i would just go ahead and change it out while your servicing the system. just a suggestion.

 

update... i changed the reciever dryer which was a task. i also bought the expansion valve but i havent installed that yet. i vaccumed and recharged my a/c after the dryer install but nothing. STILL NOT COLD. i'm very frustrated. according to this a/c manual i have the high side is supposed to be at 150-300 but its only at 100 and the low side is higher than its supposed to be...so its telling me that its either the reciever dryer or the compressor. its not saying that its the expansion valve so i guess i have to buy a compressor now right? or do you think it might still be the expansion valve?

 

also the green a/c light does come on when i push the button and turn the air on and you can hear the compressor click when i do that so thats why i thought the compressor was good

 

i still believe its the expansion valve man. think about it, that is where it switches from a liquid to a gas state, if everything else is looking good. it has to be the expansion valve. do you have a set of manifold gauges. hook them up and tell me what its reading.

also when you replaced the dryer, did you check and see if the lines have any trash in it.

 

i spent all day trying to get to the expansion valve, i removed all the clips and screws to the evaporator case. i tried just removing the bottom half but nothing will budge. so then i thought i might have to go into the engine bay and remove the ac line from the firewall but i cant even get to that either. any advice on what it could be? i really hope that its the expansion valve and not the compressor...like i said the compressor seems to be working fine but is there any way to find out for sure whether the compressor is bad or not?

 

im not sure if this applies to the prelude, but on the some model honda's there are 10mm bolts that come from the engine bay and hold the evaporator to the firewall. hoep this helps

 

ok i'll check so i dont have to remove those a/c lines going into the firewall?

 

Any update on this?

EDIT: I was trying to get the bottom black cover off too. It is coming off but there seems to be someting holding it on still.

Another thing I noticed was if I pull the black cover as far down as I can, I can slip a finger to feel around. There is A LOT of leaves in there. I am guessing that means the evaporator is bad too.


Modified by AndyD at 3:47 PM 7/1/2006

 

i wouldn't really say the evaporator is bad unless there is a leak in it andy d. you know how to check to see if the evaporator is bad right? if not pm me. leaves and trash in there is pretty common. just use a blower and blow it out carefully.

 

Ok.

Any recommendation on how to the the evaporator out?

 

according to the helms, the evaporator and case should come out as one piece. then you disassemble the case on the outside.

 

well i give up...i changed my reciever dryer then vaccumed the system and fully charged it, i bought the expansion valve too but i didnt change it because i just cannot gain access to it through the evaporator box i have tried removing every bolt imaginable but the box just wont budge and i cant get to the ac lines to take them off from the firewall because the abs is in the way. i looked at the a/c troubleshooting book and according to my tests i need to get a compressor. i can get one for 100 bucks from a 5th gen but i don't know if its the same. is it?