jaja

The A/C on my '98 GS400 isn't at its best....the air that comes out is not that cold. I compared it with my Bronco, and the air is colder in the Ford...

I tried the testing method with pressing the two switches and came up with error 21, 24, and 42.

I think 21 and 24 is the light sensor, so I'm not too worried, but 42 says its the 'Air inlet damper control servomotor' according to the service manual. Anyone know what this is?

I also measured my low side on the r134 and it was 25 PSI or .17 MPa so according to the service manual it is within the 'OK' limits.

Any ideas?

rgarjr

iTrader: (1)

It could be a leak somewhere and it lost all its charge of freon. Can you hear the AC compressors clutch engaging when you turn on the AC?

jaja

Thanks for the help....

I figured the freon was gone too so that's why I measured it... I think the low side is still within its limits. And it does sound like the clutch is engaging.... otherwise my pressure would not change.... right?

vicestan

The preasure should be measured with the a/c of I think. And as far as the compressor clutch engaging its really easy to feel, when you get in press the a/c button so it doesnt light up then press it again and you will feel the rpm on change. Basically you will feel a slight drop in engine power.

chuckb

I'm no AC guy, but my ES had same problem and it was the evapotator and or expansion valve.(I think they where all one part)

vicestan

Well I just had the expansion valve and the evaporator core replaced on my gs only because my system was leaking. Hes still maintains preasure and if after all this time hes a/c compressor engages that means that freon is still in the system and its not leaking, I mean sooner or later you do have to refill your a/c.

chuckb

mine wasn't leaking, but if the expansion valve is not opening/shutting like it should, the air temp will not be cold enough sometimes, no matter how much freon is in there.

jaja

vice -

I'm pretty sure you measure with the engine and a/c on....

I also disagree with the 'sooner or later'.... my understanding is that freon is not something that is consumed. if anyone's pressure is low that means that there is a leak somewhere.

Evaporator is the part near the blower right? sounds like a pain to fix...

But the big question is how do I know for sure what is wrong.... I had a similar problem on my Bronco, and it ended up being a pressure sensor. I changed all of them one by one, and my A/C works like a charm...

But I figure that Lexus is alot more complicated than my Ford beast.

vicestan

Freon runs out, its not a infinite source of cool air. The evaporator core is located so deep you dont even want to know. The bottom line is if your system was out of freon then your compressor wouldnt turn on at all because it knows there is no preasure. In fact I was driving an es-300 last year on a hot summer day in chicago and right then on the highway my freon started to run out and let me tell you it sucks. I refilled the car with 3 8oz bottles of freon and the a/c still runs as good as new.

chuckb

yup

vicestan

Ok maybe you have to run it with the compressor on to check the preasure, but the bottom fact is you cant say your system is leaking, you have no basis to make that assumption and jump to the conclusion that your evaporator core and expansion valve have to be leaking, unless you are rich and want the whole front dash taken apart ( and yes I do mean the whole dash everything to the wall ) then go ahead and have the car checked out for leaks, you will spend about 100 for the UV system check. But the point im tryint to make is that anyone who knows a/c systems knows that freon has to be recharged so I would suggest go to any local auto store and buy 134A freon, you can even buy the big 30 doller bottle and fill your car up, now if your a/c will be weak again after no less then 2-3 weeks then you have a leak other then that your just doing regular maintanence.

jaja

i hear ya.... i totally agree... i think i'll just get a couple of cans of r134 and recharge her up.

the only thing is that when i check the low end pressure, i figure my pressure is ok, meaning i have enough in. i have heard of overcharging the system, and guess i'm a little afraid of that.

well regardless, i guess i should just suck it up and charge her up!

thanks for the help.

vicestan

Once you hook the bottle/s up the system will take in as much as it needs and when its full you will feel there is no preasure pulling the nozle down. Then you check to see the system preasure and if its to high there is a valve for 5 dollers at any auto store that alows you to let some freon out, or you can even use the valve and hose from the charing, once ur done charging her up and u see the preasure is to high then remove the hose and install it and press on the little tab to open the valve and it will coem out of the other end where you would hook up to the freon can. Plus I see you live in cali and you must use ur a/c alot that means your freon will run out about what 6 times faster then in all season areas.

jaja

vice - i guess i talk to much....

anyway long story short - went to kragens and got the largest bottle of freon they had and pumped away. my gs now blows out cold air like my ford beast

(i just wish the low pressure valve was in an easier to access area. cause turns out my bottle had to be right side up, and... anyway was a pain in the butt... but problem solved.)

thanks for the help.

vicestan

Glad it worked out for you.