Engine stalls when AC on. AC warm at idle, cold on freeway (99 Honda Civic EX)
 

I have a 99 Honda Civic EX that is having Air Conditioning problems.

When car is at idle with AC off, the idle is fine.

However, when car is at idle with AC ON, the engine will stutter / stall / shake (but not die) for a couple seconds every minute or so like clockwork

Under normal driving conditions the AC will eventually blow cold only when going freeway speeds, and start blowing warm at idle or slower speeds.

Any ideas on this?

Re: Engine stalls when AC on. AC warm at idle, cold on freeway (atariwtf)
 

Just removed and cleaned the IACV... it had a little gunk on it. Very clean now.

Unfortunately, the problem is still there.

I wonder what it could be... AC compressor?

Re: Engine stalls when AC on. AC warm at idle, cold on freeway (atariwtf)
 

no its not the comp. you may need to charge the ac system a lil.Like 1 or halph a can of r-134( could be a little low. )or you fan for the ac condenseor isent coming on.

Re: Engine stalls when AC on. AC warm at idle, cold on freeway (atariwtf)
 

and as far as the shaking and stalling. has it always done this or just all of a suddon it started.couse my 93eg always done it, that ac comp. takes about 10-15hp to work and at say 700rpm our lil honda motors are makin like what 17-20 lol

Re: Engine stalls when AC on. AC warm at idle, cold on freeway (project4dr-eg)
 

Not sure if it's always done this stalling or not. It's a fairly new car to us.

I did a check on the low line... it's like 75 PSI!

On the gauge, this is in the middle of the "DANGER!" area.

The gauge has areas of LOW, FILLED, ALERT, DANGER.

I wonder if its overfilled??

Re: Engine stalls when AC on. AC warm at idle, cold on freeway (atariwtf)
 

holly batman lol damn thats insainly high...it should be @ 35-45psi on low side 75 is insaine suprised you havent blowout the seals. if the guage you have has a bleed vale on it, i would just (with the car off) bleed it to @ 50psi then run the car with the a/c on for and see if ir gets cool at idle(if not lower it to @ 40-45) then turn the car off and cheak it again..


Modified by project4dr-eg at 3:44 PM 5/26/2008


Modified by project4dr-eg at 3:53 PM 5/26/2008

Re: Engine stalls when AC on. AC warm at idle, cold on freeway (atariwtf)
 

The reason why your car sputters and almost stalls every couple of minutes is because that is when the compressor cycles.. If i were you, i would take the AC belt off and try to spin the compressor make sure its free and not binding. Also, when the compressor clutch kicks on, both fans should come on. An overcharged system would give you warm air also much like an undercharge, but i wouldnt count on that being your problem being that you have cold air at high speed. My bet, your compressor is shot. I would also check your battery/alternator just to be sure, (for the sputter) An extra load on a weak battery like AC could cause this.. https://honda-tech.com/forums/images/smilies/emthup.gif gl

Do this with the car off (not running) There are a few things that you can do. One do you have a temp gun? And do your A?C gauges have a temp conversion chart on the gauge so you can convert pressure into temp? If you gauges have the chart then take your temp gun and check the ambient air temp. (outside temp) then find that temp on the chart or the gauges and check to see what pressure is dircectly under that pressure for R-134a. This will give you the static charge of the system, if youre pressures are higher or lower than what is on the chart then you could be over/under charged. Now, is the 75psi with the car idling compressor on or compressor off? If it is with the compressor on what is the high side pressure? (red hose). If it is with the compressor off then the low side and high side should be within about 5-10psi of each other, that is your static pressure. I will find the conversion chart for you if you do not have it on your gauges. Just let me know. If all of the pressure check out ok check to be sure that the condensor fan is on if not that will need to be addressed. Let me know and I will try to help. PM me if you like

Re: (ambryatim)
 

I agree with check battery + charging system. Both fans prolly kick on when A/C engages. My car idles low for a second with just one fan kicking on. My low side pressure is like 25 and the A/C gets cold.

Sorry, the high pressure I read on the low side was taken with the car and AC completely off.

I am going to work on this a little more tomorrow.

First thing we'll check is the battery since that's the easiest.

The battery check will/might help with the idle issue, but will not affect the cooling of the a/c. See, when you drive the alternator will charge the battery and will supply voltage to the condensor fans, rad fan, a/c clutch etc. The battery is there mainly to start the car, but also to run the accessories on the car also. Now, if the 75psi was with the car off then what temp was it outside? Also, do your a/c gauges have a dial face that has temps on it as well?

Re: (ambryatim)
 

Ok, here is a link to a pressure calculator with pressure chart at the bottom

http://www.csgnetwork.com/r134apresstempconv.html

Now on all of these pressures you can use them for ambient temp or while the car is running to get an idea of how cold the air should be blowing out of the dash. Just find the temp on the chart that you aquired with the temp gun and match it with the pressure to see if you are in the ball park, for your system charge. Again CAR OFF AND COMPRESSOR OFF, to aquire static charge.

Re: (ambryatim)
 

awesome link.

It was about 90F outside.

Checking battery this evening. The AC is icebox cool when it's working.

Re: (atariwtf)
 

Autozone will check your whole charging system for free in a few minutes in the parking lot.

Well if it was 90 degrees out you are a few psi short of a full charge. (5 psi). You could add a little then check to see how it is cooling. I would add freon as a vapor on the low side with the engine at idle and the a/c system on. You can add it as a liquid but ONLY ON THE HIGH SIDE with the engine off.

Caution: If you try to add r-134a to the system on the high side with the a/c compressor on you could fill the can (r134a) with too much pressure and it could explode!!!

Now, if you choose to add the freon with the engine off and on the high side put the can out side in the sun for a little while, this will increase the pressure in the can and allow you to overcome the pressure that is already on your system, add only enough to bring the pressure up to where the pressure chart says it needs to be. Then test to see how it cools at idle (given the condensor fan is working). If you choose the other method (easier) start the car and turn the a/c on and let it cycle for about 5 minutes see what pressures you have, then go inside the car with a temp gun and measure the return air temp. Shoot the floor board area on the passenger side where the evap is, (return air) and take this temp and subtract 30 from this temp and then find the temp on the pressure chart and it will give you what the low side pressure should be at, if it is low add freon to correct pressure (condensor fan running) if it is high you could have a restriction or poor air flow across the condensor.

Note: If you are doubting the condensor then take a water hose and place it so you can apply water to the coils on the condensor, this will remove enough heat from the coils to help you check the charge of the system and too get it to where it should be.

Re: (ambryatim)
 

I'm going to make a video of what the car is doing and upload it. That should explain alot. I'm guessing the compressor is shot.

Re: (atariwtf)
 

A. the ac puts an extra strain on the motor when on and will make the idle dip
B. i would put my money on the pullet on the compressor isnt spinnign as easily as it should be
C.

Re: (speedooo)
 

Agreed https://honda-tech.com/forums/images/smilies/emthup.gif see previous post https://honda-tech.com/forums/images/smilies/emwink.gif

!!Never add freon through the high side!! Take the belt off and try spinning it, tell us what happens

You could also rev the engine to 2500-3000rpm or whatever rpm you cruise at on the freeway and see if the a/c gets colder, if it does it could be the compressor, like said above not turning freely enough, but if not it could be poor air flow to the condensor. Because that is all that is lackig from the test is the forced air across the condensor, from driving 70mph.


Modified by ambryatim at 11:58 AM 5/28/2008

Re: (ambryatim)
 

So if the pulley on the compressor is bad, then can I repair that without replacing compressor? or would that be "bad compressor" ?

Re: (ambryatim)
 

On the freeway the AC is fine, at idle it ..well I'll add a video soon.

You should be able to get a bearing for the pulley. A rebuilt compressor is roughly $250-$300. Check with Oreilly or you can go to rockauto.com and see what they have to offer.


Modified by ambryatim at 2:31 PM 5/29/2008

Re: (ambryatim)
 

http://is.rely.net/1-92-30002-l-J5Zy...RHu47Ah02g.gif i got a rebuilt compressor, reciever dryer, o-rings, r134a oil for 200 bucks.. look on ebay IMO dont rebuild your own unless you know what your doing and have the proper tools

Re: (jdeemseerx)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdeemseerx &raquo;</TD></TR><TR><TD CLASS="quote"> http://is.rely.net/1-92-30002-l-J5Zy...RHu47Ah02g.gif i got a rebuilt compressor, reciever dryer, o-rings, r134a oil for 200 bucks.. look on ebay IMO dont rebuild your own unless you know what your doing and have the proper tools</TD></TR></TABLE>

https://honda-tech.com/forums/images...s/emhammer.gif The prices that I am quoting are correct, sure you can find a better deal on ebay. But do the parts come with any warranty? Probably not and then you are out that 200 bucks if something were to happen. If you get it locally it is eaiser to return if you ever need too. Just my .02


Modified by ambryatim at 9:32 PM 5/29/2008

1 year warranty which is the same as most "local places"