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Punisher
06-06-2005, 05:41 PM
Anyone else notice that when their AC comes on it feels like you slapped the brakes real quick?

Every time I turn my A/C on man.. it sucks the shit outta my engine and it gives this real quick jolt (sudden power loss) like I just tapped the brakes.. way more noticeable at lower speeds.

Luis C
06-06-2005, 06:00 PM
Yeah but only for a split second, thats why most manufacturers suggest you turn the A/C on when the car is halted and not when moving (at least here anyway)

alltracman78
06-06-2005, 06:02 PM
That's the clutch in the compressor engaging. Totally normal

evilcel
06-06-2005, 06:46 PM
celicas have AC? haha, I need to get mine looked at. Hasnt worked since I got it, and now that its summer and im in central texas it needs to be fixed. I love black cars, but this blows...

temporary fix: girlfriend with ice in mouth blowing on you... or sweat like a pig till you get up to speed then roll the windows down... : )

Punisher
06-06-2005, 09:31 PM
I know that it's the A/C clutch and everything.. I'm just surprised at how much it kicks the 5SFE's ass LOL

Abacaba
06-06-2005, 11:15 PM
I've noticed that the compressors on Japanese cars are slightly bigger, compared to my other American. On my American cars, when the a/c is turned on, I don't feel the loss of power at all!! And the a/c is still ice COLD.

locker
06-06-2005, 11:26 PM
When I first got my celica it did that. But the funny part with mine was that if i turned on the AC at a standstill my car would stall out. I just disconected it

alltracman78
06-06-2005, 11:26 PM
That's because Jap cars have smaller engines. Less rotating mass.
So it's going to have more of an impact.

Abacaba
06-07-2005, 03:25 AM
When I first got my celica it did that. But the funny part with mine was that if i turned on the AC at a standstill my car would stall out. I just disconected it

I think there's an idle-up solenoid (sp?), which is probably bad in your car.

Abacaba
06-07-2005, 03:28 AM
That's because Jap cars have smaller engines. Less rotating mass.
So it's going to have more of an impact.

I didn't feel a loss of power in my '88 4cyl. Grand Am either.

alltracman78
06-07-2005, 04:01 AM
Was that a quad 4?

jezbo
06-07-2005, 04:05 AM
I think there's an idle-up solenoid (sp?), which is probably bad in your car.

You are correct, there is... but it engagues when the A/C turns on. My car does it as well, but i also have a aftermarket pully. It is going to happen do to the A/C clutch. As for the guy without A/C, my car used to be that way and I used the new R134a and it works great now.. You should try it. It can't hurt

Abacaba
06-08-2005, 05:13 AM
Was that a quad 4?

I wish. It was the base 4cyl engine. A 2.4L I think.
The engine put out close to 100hp, but it felt really strong! Like a v6.
It was a 4door grand am. :)

alltracman78
06-08-2005, 05:20 PM
I wish. A 2.4L I think.
The engine put out close to 100hp, but it felt really strong! Like a v6.
That's probably why.
Heavy internals and a lot of torque [for a 4 cly]

ALLEN
06-08-2005, 05:37 PM
I'm gonna go through my 3rd or 4th year without A/C here in Vegas', atleast its a dry heat :hehe:

From what I can tell it's gonna be to expensive to fix, atleast more than a grand in parts alone, new compressor, hoses, etc. Almost not worth it now that my car has 150k miles..

alltracman78
06-08-2005, 05:50 PM
Why hoses?
The compressor is ~ $300 rebuilt from the dealer.
You can pick up the lines at a junkyard.

If you do, replace the expansion valve and dryer. They should be ~100 new from dealer.
Might as well get O -rings for R134a while your at it.

oneof81
06-08-2005, 09:46 PM
With R-134A, you need to change the refrigeration oil. If you don't, you are asking for a lot of trouble down the road. There are alternative refrigerants that are drop in replacements for R-12. Suva MP-39 and Hotshot are just two that come to mind. And you don't need to change the access fittings with these drop-in refrigerants either like you do when you change to R-134A. As to the original comment on feeling the loss of power........it could be as simple as your car being overcharged. You really shouldn't feel a GREAT loss of power when the clutch engages. If it is properly charged, your A/C unit should only take about 5 to 7-1/2 horsepower from the engine. If it is overcharged significantly, I have seen a six cylinder engine feel like it is running on 3-4 cylinders when the clutch engages.

alltracman78
06-09-2005, 02:31 AM
Bill!!
What's up?
Why the name change?

oneof81
06-09-2005, 04:00 PM
Bill!!
What's up?
Why the name change?

Not much up........just the usual. What do you mean by name change? I hope to get my Trac back by this weekend. They have been tuning it with the new turbo. Actually, it was all tuned a couple of weeks ago on pump gas and I could have picked it up, but I thought I would go one step further and have them tune it for 110 octane race gas. Now I will have a map for pump gas and race gas. I'm hoping they can get 50-75 more wheel horsepower with the race gas. Time will tell......and hopefully time will tell this week!!!

I tried to send you a private message instead of posting here, but your private message folder is full and cannot receive any more messages. LOL

alltracman78
06-10-2005, 02:39 AM
Crap, I'll have to delete some of it.
I've been selling parts, and the damn thing keeps filling up, and up, and up....

That sounds good with the car.:bigthumbu
So how much power are you looking at?
I thought you were done since you'd hit all your goals...

oneof81
06-10-2005, 03:12 PM
You must have cleaned up your emails as I PM'd you this time and it went through. Thought it would be best instead of hijacking this thread.

Punisher
06-10-2005, 04:41 PM
Bleh.. it ain't overcharged... it was barely blowing cold when at idle/low RPMs... So I charged it up a bit.. I really do hate 134a :(

I hate the new stupid ass fittings... Makes it a pain in the ass for me to get my refrigeration gauges on.

I always used propane before in my R-12 systems... wanna talk cold.. talk 28F while cruising :)

SilverCel
06-10-2005, 04:42 PM
my ac smells like dirty socks.


whats up w/ that?

Punisher
06-10-2005, 04:44 PM
btw, 5-7HP is infuckingsane for an A/C compressor... That's around the size of a compressor in a central air system.

Murgatroy
06-10-2005, 05:02 PM
Hehe. I took mine off. I actually felt a noticible power gain. Going down hill.

AC detracts from the real joy of a car, you can't hear the car with the windows up trying to stay cool. You can hear the car with the windows down trying to go faster to stay cool.

acidice333
06-10-2005, 05:14 PM
Can I have your A/C stuff?

Murgatroy
06-10-2005, 05:26 PM
Come and get it and it is yours. The compressor and all associated hoses are gone. The condenser is still on the car, but I have no doubt it would take a few minutes to remove. I am sure there is more involved to get the rest of it. But it is open for anyone that wants it, or has a set of axles to trade for it. ;)

alltracman78
06-10-2005, 06:10 PM
Hehe. I took mine off. I actually felt a noticible power gain. Going down hill.

AC detracts from the real joy of a car, you can't hear the car with the windows up trying to stay cool. You can hear the car with the windows down trying to go faster to stay cool.

Yes and no.
I love the windows down, and keep them that way as long as possible.
But for long trips in the summer, especially with black interior, it's necessary.
Believe me, I've done 60 or so.
Unless you want a full race car, some creature comforts are worth having.
Otherwise I would just buy a CRX.

Also, when the car is stopped, it helps cool it. At least on the Alltracs. That's what I do in the summer when I let the car cool down. Turn the ac on.
5-7 hp aint' shit with a turbo.

Murgatroy
06-10-2005, 06:31 PM
I will agree with some creature comforts are worth having. That is why even my racecar had a stereo. The AC though is something I can live without. That is personal preference though. It is one of the first things I remove from any vehicle I start modifying.

How can the AC help and engine cool? I am not disbelieving you, just not understanding. It puts more of a strain on the engine. It has always caused one to overheat in my experience. To help and engine cool I would always turn on the heater (when I lived in the California desert this was hell but a must) so the coolant could also go through the heater core ( just another radiator.) Maybe with the placement of the condensor it would chill the air and pull it through the radiator, but not sitting still...

It still comes down to what you define as livable comforts. Myself I grew up driving Muscle cars that had no creature comforts. I am talking Manual brakes and Armstrong power steering. To me Chaos with her power steering and brakes is as comfortable as I get. That whole 35 miles to the gallon thing is nice to. Something that doesn't come with AC. Too many creature comforts is just more things to break with age.

Punisher
06-11-2005, 07:36 AM
Uh... Condensors can get really hot... so don't bet on that chilling the air :)

I believe what he is saying is since when you turn the A/C on the second fan comes on that's on the condensor so u have 2 fans buzzin away..I'd actually have to agree with him... I was stuck in creeping traffic for 2hrs today and I had my A/C on and my coolant temp was actually lower than when normally driving.

oneof81
06-11-2005, 05:51 PM
btw, 5-7HP is infuckingsane for an A/C compressor... That's around the size of a compressor in a central air system.

In fact it is larger. That's why it pulls down to temp SO fast. Ever notice that you can get in the car on a 90 degree day and it is over 100 in the car and it will pull down the temp in your car to a comfortable temperature in less than 5 minutes? The average house has a 2-1/2 to 3 horsepower unit. In air conditioning, horsepower equals tonnage. So your car, in effect, has a 5-7 ton air conditioner in it.

oneof81
06-11-2005, 05:55 PM
Uh... Condensors can get really hot... so don't bet on that chilling the air :)

I believe what he is saying is since when you turn the A/C on the second fan comes on that's on the condensor so u have 2 fans buzzin away..I'd actually have to agree with him... I was stuck in creeping traffic for 2hrs today and I had my A/C on and my coolant temp was actually lower than when normally driving.

What you are saying is absolutely correct. The second fan does come on when the clutch to the compressor is energized and it does lower the coolant temp when that happens. You guys really are in tune with your engine!

Punisher
06-12-2005, 01:47 AM
Doesn't take a rocket scientist to figure that out.

However it isn't exactly true either.. because if it's a hot day out.. + the underhood temp.. that condenser is going to be getting mighty hot.. and that second fan sits on the condenser.. so it's blowing hot air nearly equal to the temperature of your coolant through the condenser through your radiator.. So yes and no is it true.. It was cloudy out at the time for me and I wasn't really moving and A/C didn't have much of a load on it.. even tho it was in the 85's.. but it was cloudy so that definitly helped..

If you want your radiator to get a lot of air flow and don't want your A/C .. rip the condenser out.. and take that second fan and stick it on the outside (bumper side) of the radiator.. wire it in to either your own temp switch which you can buy at an auto store... get one that has an opening temp. of your desire.. or just wire it right into the factory radiator fan temp switch on the radiator.. not to mention when you are driving you'll be getting an assload of air through the radiator.

ALSO.. if you have a turbo'd engine with an FMIC.. that adds EVEN MORE heat.. air blows through the IC which is 1xx degree's then through your condenser and if you are using the A/C at the time that'll be up around 150-160F or better depending on ambient temps.. THEN your radiator which at that time your radiator is getting nothing but 180F air..

That's why it will be an exhaust mounted turbo for me with a very small FMIC.. and a beefy radiator and I'll have a fan on the IC as well.. I'll probably look into getting a SPAL rad fan too.

alltracman78
06-12-2005, 01:57 AM
I believe what he is saying is since when you turn the A/C on the second fan comes on that's on the condensor so u have 2 fans buzzin away..I'd actually have to agree with him... I was stuck in creeping traffic for 2hrs today and I had my A/C on and my coolant temp was actually lower than when normally driving.

Which is exactly why I said it.
This comes from experience, not me sitting in a chair, thinking about it.

Punisher-
It does cool the coolant faster.
I have a aftermarket temp gauge, and I can watch the temp drop faster with the ac on than with the heater on, vented to outside.
This is in my Alltrac. In NC in the summer. With no heatshield on the turbo.
Now, I haven't tried sitting in traffic for say, an hour straight doing this, that may work the other way.
However, sitting at a stoplight, or parking somewhere, waiting for it to cool down, this works best.

Punisher
06-12-2005, 05:00 AM
It worked for me sitting in traffic on the highway.. turned out it was a 40 car pile up! Stuck for 2hrs :(

oneof81
06-12-2005, 03:07 PM
Doesn't take a rocket scientist to figure that out.

Perhaps it does.



However it isn't exactly true either.. because if it's a hot day out.. + the underhood temp.. that condenser is going to be getting mighty hot.. and that second fan sits on the condenser.. so it's blowing hot air nearly equal to the temperature of your coolant through the condenser through your radiator.. So yes and no is it true..

Hmmmm........so you say? Lessee........the radiator is under pressure so it won't boil at 212 degrees so the temp of the coolant has to be at least 200+........at a pressure of 234 psi R-12 is 150 degrees..........hmmmm.............somehow I find it hard to believe the condensor is as hot as the radiator..........210 -150=60 degrees lower. And that is assuming you are condensing at 150 degrees. You would probably be closer to condensing at 140 degrees if the car were not moving at an ambient temperature of 90 degrees. When the car is moving and air is moving more quickly across the condensor, your head pressure would drop considerably and you would be condensing at no more than 125 degrees, a difference of 85 degrees.







ALSO.. if you have a turbo'd engine with an FMIC.. that adds EVEN MORE heat.. air blows through the IC which is 1xx degree's then through your condenser and if you are using the A/C at the time that'll be up around 150-160F or better depending on ambient temps.. THEN your radiator which at that time your radiator is getting nothing but 180F air..

What we have here folks, is a heat transfer taking place that is 120% efficient............IF the numbers were correct. But, alas, they are not. There is no way in the world that you would ever get 180 degree air going to the radiator on a 90 degree plus day with your A/C on and a FMIC. Some of the heat picked up by the air going through the FMIC would be dispersed to ambient before going into the condensor, and some of that heat would be dispersed to ambient before going to the radiator. And to top that off, the condensor is not as large as the radiator so does not entirely cover it. I would hazard a guess that the radiator would never see any ambient air entering it in excess of 120 degrees on a 90 degree day. And even if the temp was excess of this, let's say 130, you would still be dealing with a TD of 90 degrees or better to dissipate engine heat, more than enough to keep the engine cool.


That's why it will be an exhaust mounted turbo for me with a very small FMIC..

I hope you don't plan on running too much boost with that very small FMIC.


and a beefy radiator and I'll have a fan on the IC as well..

Since there is no heat soak on a FMIC, the fan won't hurt you, but, it also will not help you in this application. A fan is used to move air to aid in heat transer/dissipation when the air is static. Running a fan while the car is not moving will not help your FMIC since there is no heat in the FMIC to dissipate. And it will only be superfluous once the car is moving.

Punisher
06-12-2005, 03:39 PM
The radiator fans come on at a 194F.... So your coolant temp shouldn't even be over 200 technically.

I only saw the idea of having the A/C on making your coolant temps lower, work when I was sitting on the highway... and it was cloudy out... I've never seen my temp drop before with the A/C on.. driving.. or sitting still.

You should always just wire a switch to the second fan relay to turn it on when you want with out having the A/C on.. or you could just wire it so when the radiator fan comes on the condenser fan comes on...

And I'll be running 12PSI on the 3SGTE to begin with.

alltracman78
06-12-2005, 04:07 PM
The radiator fans come on at a 194F.... So your coolant temp shouldn't even be over 200 technically

Ha! On a hot day, my Alltrac will hit like 215 sometimes, in traffic.


I've never seen my temp drop before with the A/C on.. driving.. or sitting still.

You just have the stock temp gauge, right?


You should always just wire a switch to the second fan relay to turn it on when you want with out having the A/C on.. or you could just wire it so when the radiator fan comes on the condenser fan comes on...

That's what I plan to do, but I'm going to get new fans first.

Punisher
06-12-2005, 04:07 PM
btw, I'm not arguing with you whether it works or not.. I've seen it work.. Just saying that it isn't the "perfect" solution.. because the condenser adds heat into the whole mix.. It all depends on where you are..

You said you do it when you are sitting in your driveway? Well, if you are sitting in shade.. That would help more..

All kinds of factors come into play with the condensers temperature and the added cooling ability you will get.. Also, the condenser fan works on 2 speeds.. low and high depending on the temperature.. so if the fan is only running at low.. well you won't get much cooling to the radiator. Not to mention factors like humidity.. The higher the humidity the harder it gets to disperse heat.

So with 134a.. At 230PSI (which I'm guestimating.. I don't have any of those stupid ass adapter fittings to put on my gauges and get an acurate reading of the high side pressure) We are looking at a 140PSI.

Radiator fan comes on at 194F.. Only a difference of 54F between radiator and condenser.. Not much.. I could see coolant temps coming down a little bit.. but it would take a while and the perfect scenario for a large drop.. If it's a stupidly hot day out and it's stupidly hot under your hood.. not to mention humidity (like we've been having here lately..) It isn't gonna do much for dropping coolant temps..

It doesn't work while driving either.. not for me anyway.. I always have to run the RPMs a lot higher.. although this typically makes the A/C nice and chilly.. oh well it's a pay off.. I don't give a fuck about the engine.. if it ain't overheating .. I don't care.. I want to be cool that's all that matters.

And the fan on the FMIC might not really be neccessary at all.. seeing the turbo is going to be back by the gas tank.. I'll lose about 1/2 to 3/4PSI from the turbo to the manifold but I'll be losing a LOT of heat as well.. so running a small FMIC is all that will be needed to take the extra heat off..

http://chevyhiperformance.com/techarticles/148_0502_turbo/

They didn't even use an IC because of the 60F temp drop from turbo to intake manifold..

Not to mention no added underhood temps..

alltracman78
06-12-2005, 04:26 PM
Nothing is a perfect solution...

I do it whereever I happen to be that I want to cool the engine.
Driveway, work, traffic [usually while I'm waiting to pull into a store or whatever]
Usually not shade.

If it's cool enough for low speed, I wouldn't have it on. I only do this in the middle of the summer, when it's like 100deg out. And trust me, we have plenty of humidity here.... I'm on the NC coast....

So I use it on stupidly hot days, with stupidly hot engine temps.
Works great.

Since we're throwing # :D , If the condenser is at 160, and the rad is at 200, that's still a 40 deg drop, which is alot. Plenty for the rad. 40 deg is a large difference in temp, as far as the engine is conerned.
It will drop fast. I have the sensor reading the coolant as it comes out of the head, so it's a even bigger difference.

If you're driving at anything over say 35, you don't need it anyways. The air forced through will do a better job. This is for low speed driving or stop.

And I have less off turbo torque than you, plus it's gotta turn all 4 wheels...Don't need that high of rpms.

Punisher
06-12-2005, 07:59 PM
I don't even use my A/C for low speeds.. I generally turn it off until I get rolling.

90CelicaST
06-12-2005, 11:29 PM
I have a question. When I turn on my A/C I can feel my compressor kicking in, then kicking off, constantly. Is there something wrong with the compressor, is my system over charged, should I retrofit an R134a system?Help please?

Punisher
06-12-2005, 11:59 PM
Yes.. something is wrong.. The system is either over charged or under charged..

oneof81
06-13-2005, 12:14 AM
I have a question. When I turn on my A/C I can feel my compressor kicking in, then kicking off, constantly. Is there something wrong with the compressor, is my system over charged, should I retrofit an R134a system?Help please?

To answer all of these questions.........in order of appearance.......no, no, and no. I can't really diagnose what is wrong without some gauges on your car, but from your description, my best guess would be that you are a little low on refrigerant. There are two safety switches wired in series with the coil that operates the clutch of your compressor. One is a low pressure safety and the other is a high pressure safety. If the pressure in your system is lower than the pressure setting on the low pressure safety, the contacts will open and not allow power to energize the clutch. If you have just enough refrigerant in your system to allow the clutch to engage initially, but not enough to be properly charged, it would allow your clutch to engage, but when that happens, the compressor starts and the low side pressure goes down below the low pressure safety setting, which opens the contacts stopping power from going to the clutch and the clutch disengages. Once this happens, the low side pressure and the high side pressure try to equalize and the low side pressure comes back up, energizing the clutch again, but then once the compressor comes back on line the low side pressure goes down again and this scenario repeats itself over and over. Have someone put gauges on your system and confirm this. You most likely only need a pound or so to rectify this problem. From your given information, this is the most likey answer to your problem in my estimation. The system would have to be drastically overcharged for the opposite (high side pressure safety) to happen and it would not happen so rapidly as it would take longer for the high side pressure to reach the high pressure safety setting.

90CelicaST
06-13-2005, 12:21 AM
Im sure this is what is happening. We had the gauges on, but I don't know what to look for. It seemed like the cylinder of R12 we had was low, so I'm pretty sure that this is what is causing this. I'm going to have somone try to charge it. And thanks for the help. :bigthumbu

BEAMS
06-13-2005, 01:04 AM
I found this portable 12v ac. Its used for race cars, or so they say. Makes sense to me, because you can just take it out when you dont need it. Im not sure how well it works, but its just something i might like to try since my ac doesnt work and i just dont want it on my engine. I like having ac during summer, but not at all during winter so i really like being able to take the ac out completely.
12-Volt Swampy SpaceKoolr Model T154
http://www.swampy.net/hprices.html

Punisher
06-13-2005, 01:37 AM
Don't bet on it working.. any REAL A/C system would kick the shit out of your alternator.

Something makes me believe that those units use a device called Peltiers (thermocouplers) to cool water.. which is sent through tubing and air blows through the tubing to send out cool air.

Don't bet on that thing working well at all, I wouldn't even waste the money.