a/c fast idle switch/relay?

[spoon611]

I just had my a/c converted to r134. The a/c blows cold air just fine, but the fast idle relay keeps clicking off/on. I can hear the clicking inside the car. I checked the compressor clutch while the relay clicks off/on and it stays engaged the most of the time. Is there a way to troubleshoot this so that I can narrow it down to what I need to do? Maybe just a mere cleaning of the relay? I dunno. I also am not sure what and where the control is for the fast idle.

Also, when I first had the freon on loaded the a/c would go off and on whenever it wanted to. I would push the a/c button and it would either go on or not go on. Sometimes while it was running it would just switch off by itself. I thought it had something to do with the actual switch that's on the head unit because it would go back on after smacking the dash a few times, but I'm not positive.

I have a manual with a carb. Keihin compressor I think.

[Blkblurr]

The clicking you're hearing is the compressor kicking in and out. Sounds like your freon is still low. You also have a pressure switch that prevents your compressor from running if the freon gets too low. Put in some leak sealant you can buy from Advance auto. It stopped the leaks I had in mine. I also converted mine to R134 and found the adapters for the new freon leak. so I pulled them off.

[Vinny]

Usually if the clutch cycles on and off on its on its caused by the low pressure switch. If the cycling gets worse as time goes on then you have a leak somewhere and are loosing freon. Did you change your filter dryer?? Did you have the system evacuated and pull a vacum on it before you reserviced it to see it it would hold pressure? Also if the system was open for any length of thime did you have it flushed and change the O rings. Biggest question is do you have the proper amount of oil in the system? You can't REALLY use the all in one oil and r34 in one can because the ratio isn't correct to ge the right amount of oil in the car. if you over service it will become oil logged and won't cool after so long, under serviced you'll burn your clutch up. AC isn't one of those things you can just add freon and be done, 9 out of 10 times you need it done professionally or your wasting your money not only due to lost freon from leaks but burned up parts from inproper servicing or contaminates from not flushing an open system. Any time a system is open for even a short period of times, especially here in GA where its humis you MUST change the filter dryer.

[Vinny]

If your compressor looks like this http://www.partsamerica.com/product_images/AAP/FAA/57871.jpg you have a keihn

If it looks like this http://www.partsamerica.com/product_images/AAP/FAA/57353.jpg

or this http://www.partsamerica.com/product_images/AAP/FAA/57350.jpg

You have a denso

If you have a keihn they are NOT 134A friendly

[Blkblurr]

Good info Vinny. You get a can of oil separate from the R134 freon when you buy the conversion kit. My system had a small leak in it so I just did the conversion by adding the new oil and then adding the R134. I agree it isn't the best way to do it but my a/c works great and has not lost pressure since I put the leak sealant in it.

[spoon611]

Well I had the vacuum pulled in it and had 8.5 oz can of oil plus 2 cans of freon put in. It may possibly be a little low on freon, but I didn't know if I should go off of the sight glass with r134.

I never had anything replaced in it...dryer, orings, nothing. I had no money to do any replacing, just wanted a/c for this summer. I had a 20 dollar can of stop leak from autozone put in it, it seemed to seal it off. I've had freon in it for about a week now without any loss in coldness. No need to lecture me about replacing stuff..I know :rolleyes: I am just short on cash...ya'll know about that right? LOL

At times when the fast idle does switch on/off...the compressor clutch will still be engaged....can you explain that part too? Also, can i trust the sight glass for filling the freon? Thanks


Oh yeah...it's definetely a Keihn

[Blkblurr]

The idle speed is increased when the compressor is running because of the load the compressor puts on the engine. The higher idle speed also helps the compressor pump more freon so you get more cooling when idling like when your in a traffic jam.

[spoon611]

The idle speed is increased when the compressor is running because of the load the compressor puts on the engine. The higher idle speed also helps the compressor pump more freon so you get more cooling when idling like when your in a traffic jam.
Sorry, I should have been more specific....
Why is the fast idle switching off/on and teh clutch is still engaged? I'm thinking there is something wrong with the fast idle relay, but not sure. I understand why the fast idle goes on, but normally if the fast idle goes off the clutch is disengaged too. hope I cleared that up a little.

[nswst8]

So your having problems again glad you finally got the vaccum pulled on the system, Sorry I couldn't help you on that, just saved my neighbor $700 on his A/C.

But anyway, what I'm concerned about is the 8.5 Oz of oil this sound to be alittle bit to much especially if the freon was premixed with freon, oil, sealer. I did this to my Dad's plymouth and couldn't figure it out until I checked the correct amount of oil.

You see even with not charge in the system there is still residual oil left in the system some in the compressor, evaporator, condensor and the receiver and filter/dryer

This is what the book describes: Add oil after replacing these parts.
Condenser 30cc (1fl oz)
Evaporator 30cc (1 fl oz)
Line or hose 10cc (1/3 fl oz)
Receiver 10cc (1/3 fl oz)
Compressor......When a new compressor is installed, drain 30cc (1 fl oz) of refrigerent oil the suction fitting on the compressor, unless you are replacing any of the above parts. Then pro-rate the amount you drain by the amount you should add for the other part(s).

So again it sounds to me like you are oil logged, after you had it vaccumed down I would have just added the Pre-mixed without any extra oil.
What you can try and do is bleed off the system and be careful that the vaccum is not lost and then add straight freon.
Hope this helps, LOL
Phil :cheers:

[spoon611]

We took out all the freon that was in there before we vacuumed it. After it was vacuumed they put in the can of oil and 2 cans of straight freon, no oil added. Does that clear up anything? Maybe more freon?

I'm really not having any problems with the air as long as the clutch is engaged. I'm just trying to narrow down how to keep the fast idle on while the a/c is on. You're saying that maybe because there's too much oil in the system that it is causing the fast idle to malfunction?

[Blkblurr]

The oil they put in for the conversion is so that it is compatable with the new R134 refrig. It's not a full shot of oil but enough to stabilze the old oil.

[nswst8]

its the idle adjustment screw located at the carburator, your idle is suppose to be set at 700 +/- 50 RPMs (In Neutral for MT / N or Park for A/T) Idle speed A/C off.

After charging, adjust the idle speed with A/C on:
Apply the parking brake and block the wheels
Headlights..................OFF
A/C temp lever............Cold
Vent and Recirc buttons...ON
Fan Switch.....................High

Adjust the idle speed by turning the idle adjusting screw in or out as required.

Now with only the A/C on and in neutral your RPMs should be at 750 +/- 50 RPMs
There is a idle boost diapham at the adjusting screw this could be fouled up.
Hope this helps. LOL
Phil :cheers:

[spoon611]

its the idle adjustment screw located at the carburator, your idle is suppose to be set at 700 +/- 50 RPMs (In Neutral for MT / N or Park for A/T) Idle speed A/C off.

After charging, adjust the idle speed with A/C on:
Apply the parking brake and block the wheels
Headlights..................OFF
A/C temp lever............Cold
Vent and Recirc buttons...ON
Fan Switch.....................High

Adjust the idle speed by turning the idle adjusting screw in or out as required.

Now with only the A/C on and in neutral your RPMs should be at 750 +/- 50 RPMs
There is a idle boost diapham at the adjusting screw this could be fouled up.
Hope this helps. LOL
Phil :cheers:
LOL, you know I did that? I just increased my idle speed up with the a/c on until I could figure out what's wrong. Now with the a/c off it idles around 1200. Better then it shaking the hell out of the car I guess.

[Mac]

OK what I think the clicking you are hearing inside the car is the A/C delay relay. When you turn on the A/C it energizes a delay relay (under right side of dash below the blower). After 0.5 seconds this relay tells the ECU that the A/C is on. Then the ECU sends signal to the idle boost solenoid (left side of engine compartment) which raises the idle.

So if you are hearing a clicking inside the car, good chances that it is the delay relay. If that doesn't stay energized your idle won't increase.

[spoon611]

OK what I think the clicking you are hearing inside the car is the A/C delay relay. When you turn on the A/C it energizes a delay relay (under right side of dash below the blower). After 0.5 seconds this relay tells the ECU that the A/C is on. Then the ECU sends signal to the idle boost solenoid (left side of engine compartment) which raises the idle.

So if you are hearing a clicking inside the car, good chances that it is the delay relay. If that doesn't stay energized your idle won't increase.

That sounds more like what I'm experiencing...what do I do to fix this? Replace the relay? If that's so, how do I get to it and what does it look like?

[Mac]

I see that you have an 89 DX. I don't want to steer you wrong, so let me tell you that the info I'm giving you applies to an 88 LX. I'm not sure if there are any differences. I'm hoping they are the same.

Anyway if your delay relay is chattering there are other things that can cause that, but the relay is a good place to start.

Go look under the dash on the passengers side. Find the blower motor (big black thing). Then look to the right of that. There should be a small plastic box (mine is white) with a connector on it. First make sure that the connector is on all the way. Then start the car and turn on the A/C. When you hear the clicking, feel the box and see if you can tell that is where the clicking is coming from. If it is, go to junk yard and get one and plug it in and see if it works.

Hope this is some help.

[spoon611]

Sounds like a good start to me Mac :). I'll have to get to that when I have some time. So much going on right now, can't really go out to a junkyard and pull parts. But I plan on it since I have other parts I would like to salvage.

Did you have this problem and if you did, did this fix it?

[Mac]

No never had that problem. The problem I had with my A/C was a leak. I decided to stay with R 12 and got a new compressor, dryer, and condenser. Evaced. vacuumed, and changed all the o-rings. Now it works fine.

BTW you did add too much oil. Our system only requires approx. 4 ozs. Too much oil will limit cooling abilities. If you can afford it I would suggest that you evac, vacuum, and change all o-rings (not really that hard) and go back to R 12. Our system was designed for R 12 and I feel it works best with it. Your A/C might be all right now but who knows how long it will last and if anything will get damaged.

Oh yeah, it is recommended that whenever you open an A/C line that you change the receiver/dryer. It is there to remove moisture in the system and when a line is open, even for a short time moisture will get in and the dryer will be contaminated and it's ability to remove moisture will be lessened.

[Morpheus]

The Denso one looks better.

[98serwtricks]

Geez - I was gonna attempt to switch the Accord over to the R134A, but after reading all the A/C conversion posts - I'm not sure now.... I'm gonna have to research it further...

[nswst8]

I've had the conversion since they were trying to charge $1200 for the conversions kits at the dealerships. "1997" aside from a small leak that needs to be recharged every 18-24 months all systems leak in one form or another.

I never replaced the dryer, o rings or compressor. nor did I remove the compressor to drain and replace the old oil.

Now if your system has been empty for awhile and you have no freon at all then I encourage you to replace the dryer. But if your system just stopped cooling and you system is just low "DO THE CONVERSION"

Again I've done the shade-tree conversion and "I AM COMPLETELY HAPPY WITH THE RESULTS"

There is only a 4 degree difference between R-12 & R134a, you only need to use 80% R134a in the conversion. add only a 2 1/2 oz. can of oil only if you are using straight freon. I use the pre-mixed sealer/freon/oil and have had no problems.

Hope this helps
Phil :cheers:

[spoon611]

It's kinda funny this got bumped up. I tried running my A/C after the car sat for a week and the clutch seized up on me :mad: . It started smoking from the friction. Looks like I'll be 2 down at 75 :werd:

[98serwtricks]

...all systems leak in one form or another.

I never replaced the dryer, o rings or compressor. nor did I remove the compressor to drain and replace the old oil.

...But if your system just stopped cooling and you system is just low "DO THE CONVERSION"

...you only need to use 80% R134a in the conversion. add only a 2 1/2 oz. can of oil only if you are using straight freon. I use the pre-mixed sealer/freon/oil and have had no problems.

I may just try this. I saw some kits at the local auto parts store - I'm going to check them out closer to see if they'll work

[nswst8]

Try not to use the aluminum fittings if possible. I got a kit from Napa but you can buy individual fittings.
Just remember you do need to pull a vacuum on the system 45 minute min.
Good Luck
Phil :cheers: