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nokia8860
06-26-2003, 12:01 PM
This started the other day. But I have my AC set to 68 on auto and it works. But the other day till now its acting weird. Outside temps in the 100 and when I gas the car, normal driving, the ac shuts off till I release the gas then it comes back full blast. This happens in either auto or manual mode. Also regardless of temp setting.

Funky huh. Its like the car is saying either you want me to go or you want to be cold pick one.

But never happened before till the other day. Its not like its something major for me to repair but if anyone has any tips let me know.

Denlasoul
06-26-2003, 12:21 PM
I thought that items driven by accessory pulleys shut off under full throtle. That could explain why it turns off. Have you noticed this before in high temps?

DLS

Luwin1026
06-26-2003, 12:56 PM
Originally posted by Denlasoul
I thought that items driven by accessory pulleys shut off under full throtle. That could explain why it turns off. Have you noticed this before in high temps?

DLS



Originally posted by nokia8860
when I gas the car, normal driving, the ac shuts off till I release the gas then it comes back full blast

nokia8860
06-26-2003, 01:37 PM
so that means its normal?

5.52
06-26-2003, 01:58 PM
really really ..does not sound normal to me...

in fact, it sounds like the a/c compressor is disengaging (stopping- cutting out) due to a fault condition(s) that must remedied...the disengagement/ stopping is an MB built in safety to prevent further hvac system problems failure(s)

your fix may be as simple as a loose wire on the a/c compressor or as deep as leaky evaporator or combi

I understand that there are klima control issues on 202s that are known to complicate your exact condition further.,,that may need to addressed as well

I'd suggest taking it pronto to an MB a/c specialist (system issues are easily diagnosed) --we have some hot, hot, HOT! temps rearing their ugly head here in the South Bay with more to come!

A proper working MB a/c system should not cut out as you have described. I have enthusiastically driven a variety of MBs at triple digit speeds with a/c fully operational.

fwiw- I'm driving my ancient underpowered '92 W124 today (R12 system) because the engine temps remain a tad above 80 even in stop and go driving oh, and the a/c is North Pole blitzen freezing my arse off!

>by comparison the '02 C320 Wagon just cools adequately on full tilt with 2 in the car

also, fwiw- don't take your car to Smythe 'cause they are knee deep in ML recalls and fixing a number of '03 SL500 issues. Good luck!

5.52

kameraguy
06-26-2003, 02:00 PM
If you want we can check for any fault codes in your system. I can swing by whenever you are free.

5.52
06-26-2003, 02:05 PM
High Ambient Temps will especially strain hvac and cooling systems- - that's why there's a flood of a/c, hvac, and cooling system repairs that occur around this time of the year

minor weaknesses may become major ones as they are taxed to the limit

5.52

nokia8860
06-26-2003, 02:16 PM
I might add though that after about 15mins into the drive on the freeway it becomes back to full blast regardless of throttle position. weird huh. guess its time to open up the hood and check out whats going on.

anyone have the diagram for the cooling system on their coffee table they wish to share?

I should adds its not that cold air that cuts off. its the fan that stops blowing. You could put your hands on the vent and still feel the cold coming out just no fan pushing it.

JRE320
06-26-2003, 02:46 PM
Originally posted by kameraguy
If you want we can check for any fault codes in your system. I can swing by whenever you are free.

You got a diagnostic equip. to get the faulty codes?

nokia8860
06-26-2003, 02:52 PM
sure chris. that would be cool. hopefully it will generate a code like:

A03FY = Its normal you dont have to spend money to fix it.

but yeah let me know when you can visit.

Brabus
06-26-2003, 04:31 PM
That was a problem on an old Ford Van that we have. I don't exactly know why. Let me ask my dad what the problem could be... but it did the same exact thing that you describe but all the time reguardless of temp.

nokia8860
06-26-2003, 04:39 PM
I was testing it on the way home. It only cuts off when the ac compressor is on. If set on ec the blower just keeps on going. Strange though. About 20mins into my commute it no longer cuts off.

grrr....

nokia8860
06-27-2003, 09:04 AM
Ok on my way to work. 86-90 deg outside. Ac on auto at 68. Guess what... it works normally.

I will see on the way home when its over 100

5.52
06-27-2003, 10:05 AM
something is failing: monvalve? control unit? interior temp sensor?

the system should be working 100% of the time if operating properly....

an MB hvac pro will be able to diagnose- - as soon as it fails consistently

wishing you luck that it is just a hiccup!
5.52:cool:

Stay Cool!

kameraguy
06-27-2003, 10:41 AM
Originally posted by JRE320
You got a diagnostic equip. to get the faulty codes?

When my car had the misfiring issues I bought the OBDII scanner HW for my palm pilot. It isn't anywhere near the ones the MB techs use, but it lets you see the TCs and reset some of the basic ones.

and btw....no e-mail from you Jun. Are you still interested? Have you even seen my last e-mails?! :rolleyes:

J Irwan
06-29-2003, 07:24 PM
Originally posted by nokia8860
I might add though that after about 15mins into the drive on the freeway it becomes back to full blast regardless of throttle position. weird huh. guess its time to open up the hood and check out whats going on.

anyone have the diagram for the cooling system on their coffee table they wish to share?

I should adds its not that cold air that cuts off. its the fan that stops blowing. You could put your hands on the vent and still feel the cold coming out just no fan pushing it.




Joey,

Last time my friend's 99 CLK320 has the same sympton like yours..

I couldn't recall exactly what was the fix, however it was some sort of sensor ...


Regardz,

J Irwan

CKlasse
06-29-2003, 10:46 PM
It sounds like your problem occurs when the pressure isnt stabilized yet -- Upto 10 minutes from the engine start and idling at 1500rpm.

First thing first.. check the compressor clutch. Is it working while the A/C blower stop working (in your case, step on the gas pedal while the car is on PARK, and have someone look at the A/C clutch). If it's working, that means the problem exists on the BLOWER (motor, power transistor, relay, etc).

If clutch stops as the A/C stops blowing during the open throttle condition, it could mean that the ECM intentionally cut off the A/C due to a malfunction somewhere......

Malfuntioned Ambient Temp Sensor (front driver side grill), Passenger compartment temp sensor (passenger side dashboard), water temp sensor, evaporator temp sensor, malfuntioned thermostat, and the magnetic clutch itself (??)

It would be hard for us to help you without being there :(

This is why diagnostic guys get paid $120/hour at major dealerships :eek: :eek: :eek: :eek:

nokia8860
06-30-2003, 07:13 AM
Kameraguy came over last friday we pluged in the obdII scanner and no codes came up.

I hear you on the diagnose part of it but right now im not feeling like parting with my cash right now.

Glad it got cooler for the time being. :)

J Irwan
07-01-2003, 12:03 PM
Originally posted by nokia8860
Kameraguy came over last friday we pluged in the obdII scanner and no codes came up.

I hear you on the diagnose part of it but right now im not feeling like parting with my cash right now.

Glad it got cooler for the time being. :)


Is it still acting up or you got it resolved..?


Regardz,

J Irwan

nokia8860
07-01-2003, 12:22 PM
Originally posted by J Irwan
Is it still acting up or you got it resolved..?


Regardz,

J Irwan

its fine now. do you know what was changed on your friends car?