JL35

Hello all,
This is a totally new car to me and also my first Acura/Honda. I'm a regularly a 90's BMW person

So I received the car with a functional AC except when turned on the idle surges very badly. Undrivable.Now at this point, it seems that my freon has leaked out in a time span of a week. Blower works great, everything is fine now except that the AC does not blow cold air. Only hot air. Also there is a easily noticable hiss sound coming from the vents inside the cabin when the AC is trying to work, which seems normal to me but you all know better so I don't want to be the judge of that.
I am hoping that the problem is a simple leak, but I also suspect that the compressor could be bad. The slow leak is at least creating some optimism for me.

So I am not sure what I should do. I have always worked on my own cars so no problem there but I hardly understand AC systems. How am I supposed to diagnose the problem?

Karanx7

iTrader: (2)

Search on YouTube: how to find an ac refrigerant leak. Find the leak, fix it, then refill the refrigerant.

I have used dyes and UV light.

JL35

Yeah I'll see what youtube can do for me. Where in the engine bay is the AC compressor?

Karanx7

iTrader: (2)

It's directly under the alternator.

JL35

I bought UV detection fluid to put in the AC lines and a UV flashlight.

Now I'm noticing that the Idle Air Control Valve was actually not the problem with my surging Idle as that issue has resurfaced. I replaced the part and the surging went away but only temporarily. A day after installing the new part, the check engine light went off and my idle started surging from 1000rpm to 1500rpm oscillating about three times per second, but before this would only happen with the AC on. So the car is surging idle very bad ad it isn't the IACV. Could this be my AC condenser?

Karanx7

iTrader: (2)

You have a vacuum leak. No, it cannot be from the A/C compressor.

It's either a faulty IACV, or you have an actual vacuum leak somewhere. You can search on YouTube how to find a vacuum leak. If you don't find anything, it's probably the IACV again. If swapping in a new one fixed it temporarily, then it's probably involved.

JL35

Ok so I put the UV stuff in and I'm waiting a couple days and I'll check for leaks.

Also I took the new IACV from autozone off and installed the old one and.. Surprise, the car still surges but now worse than before. 1000-2000rpm oscillation. I have an OBD cable to USB and I need software to read engine codes and see what's going on.

There could also be a possible bad AC relay, according to my brother and his trusty mechanic. He said the mechanic tried fixing the relay but that may not have been enough or it didn't hold over so a new one might be in order. Any other possible faulty relays that could be the cause of the surging? I'm betting an OBD scan will reveal this.

Another thing to be noted is I am in a very hot an arid climate, where this car very only very recently introduced to.. Keeping in mind I just got the car from my brother who drove it for two years without a hitch in San Diego, CA where the air is thick and usually cool. I live in a California Desert.

Karanx7

iTrader: (2)

So swapping the IACV makes the problem worse/better, and you think the AC is the problem?

How would the AC system cause an idle surge? The idle is increased a little bit to compensate for the load when the AC compressor kicks in, but that's not enough to cause a surge. If you have no pressure in the AC system, then the compressor will never kick on.

JL35

The part where the IACV becomes involved with the AC is when there is a need for more accessory power so the valve opens up to let more air in the system. Obviously, the AC puts a load on the system since it is accessory driven so the engine has to work harder. This is where the idle air control valve comes in; a flap opens and lets extra air into the intake to increase RPM and compensate for the extra load. This is what all of the accessories do which now makes sense to me because this valve doesn't just open when the AC turns on. There is a valve that opens up and sometimes they go bad and flap around creating the surge and sometimes they get stuck in an open position causing a high idle. I am experiencing both of these.

The A/C is what initially caused the idle surging for the first few days this was happening, the problems with the AC not working and the IACV seemed to coincide which made this confusing. Anyway, I got a code reader today and promptly scanned the system. It gave me code "p0505" which is "Idle Air Control System," and I don't know what could be wrong at this point. I've checked for vacuum leaks and found nothing but a vacuum leak wouldn't cause such an aggressive idle and the surging. A bad IACV would cause the idle I am experiencing but I don't have a bad IACV. I also made sure that the electronic connection wasn't bad. I disconnected the battery because I was told that is how you reset the ECU.

Karanx7

iTrader: (2)

Oh, I'm sorry if you thought I was legitimately asking you how the idle works. It was a rhetorical question; I know the ins and outs of this car completely. That's why I said the increase in idle isn't enough to cause a surge.

I'm not sure what the stock idle comp is, but it won't cause the idle target to raise enough for DFCO to kick in. There is something that is causing your idle to increase to DFCO, and that is causing the surge. The car will never purposely set an idle target higher than the fuel cut value. This means that you absolutely are getting more air than the car wants, which indicates a vacuum leak.

You have a vacuum leak. It's just a matter of finding it. My bet is the IACV which seems pretty obvious. The IACV seems to be leaking just a little too much air in. This means that with the A/C idle comp off, the car wont hit the DFCO. However, the A/C load comp is probably increasing the idle target value to the fuel cut.

JL35

I was just trying to link the IACV and the AC together since both went out at the same time.

As for DFCO, my car tends to surge from 1k-2k now and sometimes 1k-1.8k but more often now it will keep a consistent idle speed at 1.5k. DFCO seems to consistently be present with rpm above 2k for any gear. The car drives like sh*t when its lower than those rpm in any gear. Also now the car seems to have adopted a mildly aggressive jolt or kick anytime you let on or off the throttle. It doesn't allow for a smooth ride at all.

Well the bottom line with my situation is that there are no vacuum leaks outside of the IACV since I've already checked all areas where a vacuum leak can occur. I guess it is possible that I missed something with the vacuum leak check but I really doubt that's possible because I soaked the manifold and any vacuum lines I could find with carb cleaner and pinched off the line from the brake booster. I was very thorough but I guess in my naivety with this car, I could have easily missed something.

Other than missing a vacuum leak I can only think that the ECU could be the problem, like as if it was bad.. But I doubt that could be the problem since these ECU hardly ever have serious problems. I also don't think that it is a coincidence that the car started acting like this as soon as it was brought into a hotter climate since it was fine before. The only reason that I can think that the ECU is the problem is because my IACV is good, as well as the coolant lines and the molex cable. I'm really dumbfounded on this.

Any way there could be a fuse or a relay that went bad? I know that one of my AC relays is bad, not related to the IACV, but maybe when goes out it can potentially take others with it?

Karanx7

iTrader: (2)

I don't understand. Are you illiterate? It's your IACV that's the problem. Why do you keep saying that you have a good IACV? You don't.

Whether it's a relay or a faulty part, the issue is coming from the IACV. Unplug the IACV and see if that makes any changes. If so, then it is being powered. Buy a new OEM IACV and install it.

YeuEmMaiMai

I'm going to give you the best advice in this thread to help you troubleshoot the problem you are having

1. you replaced your ICV...you need to disconnect the battery and come back in 15 minutes and reconnect it.
2. make sure all of your accessories are OFF
3. Start car and let run for 15 minutes

See if problem remains

Karanx7

iTrader: (2)

Also, here's a thread that might help you:
https://acurazine.com/forums/second-...g-iacv-927263/

There's apparently different part numbers for aftermarket ones, with one being an economy model. You should be good if you get the one that the thread specifies. If you already got that one, it might be bad or an improper install/ECU reset.

JL35

Thanks a bunch for the link.

The part Autozone said was for a 03 Cl Type-S (AC4069) according to AZ's parts database which many other websites say fits many Honda and Acura from a wide spectrum of years spanning from 03 and up. This is the part I got from them and it just turns out that is incorrect information based on my results.
AutoZone is a bunch of tools that will unenthusiastically and moronically sell you wrong part, which is mostly what I learned from this.

Going to order this part; allegedly the correct one.

"I don't understand. Are you illiterate? It's your IACV that's the problem. Why do you keep saying that you have a good IACV? You don't."
Karanx7, for someone with over 3.5k posts it comes at quite a surprise for me to see that you can so easily talk down on someone for practically nothing, almost as if you're trying to arouse drama. I said I replaced the part, did I not? Illiteracy, oh the irony. I'd like if you would can the rhetoric and the attitude.

You have been helpful other than your remark.

JL35

Yeah I did reset the ECU properly before but now I am confident what the problem was. Thanks man.

Karanx7

iTrader: (2)

Look at it from my perspective:

You post about an issue in your car. I tell you that you have a bad IACV. You go on about a bunch of other things. I tell you that those things are unrelated, and that it's your IACV. You tell me that your IACV is good. I again tell you that it's your IACV. It turned out that it was your IACV the whole time.

I wasn't trying to be rude (though I couldn't care, I'm not getting anything out of helping you), but just trying to help you fix the problem instead of chasing a bunch of other leads. Either way, hopefully the right part fixes your problem. And I agree, AutoZone employees are generally idiots who think they're smart.

JL35

Yeah I'm sorry that I made this thread of mine multisubjective and hard to follow, that is the last thing I want to do (especially since you are helping me with your extensive knowledge of the vehicle). It got confusing since I was discovering multiple problems at the same time. I'm also dealing with another problem with a window regulator I had someone install but I won't get into that.

I can respect a rhetorical question as well as the next guy but I am going through a lot of shit with this car plus other things so it's easy to go off-base about something. I appreciate your input and all, I hope it does make you feel good to help out at some points at least.
Anyway, that thread helped a lot man. I wish I found it sooner but hey, I probably would have never realized that I had the wrong part because it fit perfectly. In fact I'm saving $30 now because the correct part is cheaper and on its Prime.

Annnnnnd Pep-boys has been sooooo much better for the hundreds of times I've been there compared to the three or so times I've been to AZ.. Just sayin.

I'll let you know what happens when I try the right part and reset the ECU.

JL35

I'm still waiting for the part to show up for the IACV.

Anyway, I've found out what the HVAC problems were. Me and my mechanic saw that the blower resistor was probably blown and the connection was melted obviously because the resistor blew. CarID has a kit by dorman which I know is a company from Taiwan but I've had big problems with a window regulator from them before because of the connection. https://www.carid.com/2003-acura-cl-...heating-parts/. I actually think the resistor is still good because the AC will turn on when we adjust that connection into the right place. Maybe I can salvage the molex?

Ok so we found out one of the big problems, yay. We also found the leak, which was the valve on the high pressure side of the AC lines. More yay. There is still something very wrong with the system though and my mechanic narrowed it down to two bad parts; the expansion valve under the dash, or the AC compressor (which I dread replacing). I'm hoping that the expansion valve needs to be replaced so I will do that one with the OEM valve before touching the condenser and then see what those results yield.

Anyone know of any threads containing expansion valve replacement?

zeta

iTrader: (1)

The only thing I could find is a post from the guy below:

https://acurazine.com/forums/2g-cl-problems-fixes-70/dryer-reciever-replacement-during-ac-repair-723768/#post10871092

There is not much guidance in the Helms manual either, other than a parts blow out diagram of the evaporator components, showing the EV location, which looks similar to the one below:

https://www.acuraoemparts.com/auto-p.../a-c-unit-scat