My low side AC pressure W203 2002 C230
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2002 c230
My low side AC pressure W203 2002 C230
My low side AC pressure W203 2002 C230
I got a set of guages from Auto zone.
It was 61 degrees F out.
I checked the low side only, before turning the AC on, then after a few minutes of it running full blast, then after 8 minutes.
The pressure would change based on how hard I pushed down.
If I pushed very lightly once it just went up to 45.
But most of the time, or perhaps I was pushing hard every time, it was in the
70-80 range.
I did accidentally have the heater running a few minutes before I switched to AC though.
This is the low side.
I did notice that my AC gradually started taking longer to blow cool air over about a year's time.
Is it a bad reading, or does that mean it is fully charged, or is it possibly over charged?
Thanks.
Oh and I didn't check the highside because there it says that I can't open it while the system is charged. I figured it meant the cap on top.
I do have more information as to what it could be, but I'd rather just get answers on what the pressure means for now.
Thanks a lot.
I got a set of guages from Auto zone.
It was 61 degrees F out.
I checked the low side only, before turning the AC on, then after a few minutes of it running full blast, then after 8 minutes.
The pressure would change based on how hard I pushed down.
If I pushed very lightly once it just went up to 45.
But most of the time, or perhaps I was pushing hard every time, it was in the
70-80 range.
I did accidentally have the heater running a few minutes before I switched to AC though.
This is the low side.
I did notice that my AC gradually started taking longer to blow cool air over about a year's time.
Is it a bad reading, or does that mean it is fully charged, or is it possibly over charged?
Thanks.
Oh and I didn't check the highside because there it says that I can't open it while the system is charged. I figured it meant the cap on top.
I do have more information as to what it could be, but I'd rather just get answers on what the pressure means for now.
Thanks a lot.
Last edited by Onericali; Feb 6, 2011 at 05:42 PM.
Thread Starter
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Joined: Aug 2010
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2002 c230
I'll check first thing tomorrow.
To check high side pressure you do not have the AC running correct?
Am I supposed to push down very hard? It doesn't seem to snap in place. I'll have to get someone else to give it gas I suppose.
Thanks and I'll get back with you tomorrow.
To check high side pressure you do not have the AC running correct?
Am I supposed to push down very hard? It doesn't seem to snap in place. I'll have to get someone else to give it gas I suppose.
Thanks and I'll get back with you tomorrow.
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2007 c230
Normal reading with the AC off should be 80-100 with the AC FULL MAX it should be in the 25-35 PSI. And no not a lot of gas(pedal) pressure.. just a slight increased amount for maybe 1K + 2K more then normal consistently for a couple of seconds and see if the low side moves down? Keep in mind there hypotheically you have a leak a very very slow one and you need to "recharge" once you sealed the leak you cant just pop a bottle of 134A and gauge use the attached gauges to measure the amount of freon to put in. Freon is "weighed" And our cars are very specificually so if reading those gauges and/or finds the problem and it's probably a leak bring it to the professionals because overcharing with FREON with destroy the Compressor
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Thread Starter
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Joined: Aug 2010
Posts: 95
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2002 c230
Ok it was 70 degrees outside.
Got both highside and low side to clamp on.
The readings with the car off were around
Low side 55, High side 65
AC full blast after 10 minutes with windows down and one door open at 1900 RPM (idle is 0900)
Low side 85, High side 65
Closed door but left windows open
Low side 95 High side 60
End note: Damnit, I feel like when I took the guages off I leaked some.
An indy shop already told me my compressor is bad and that the SAM is also faulty. (2400 total to fix)
I wish I asked them more about their diagnosis.
These pressure readings seem to indicate the same thing. If low is high and high is low.
I'll hook it up to my code reader when I get it in the mail.
Got both highside and low side to clamp on.
The readings with the car off were around
Low side 55, High side 65
AC full blast after 10 minutes with windows down and one door open at 1900 RPM (idle is 0900)
Low side 85, High side 65
Closed door but left windows open
Low side 95 High side 60
End note: Damnit, I feel like when I took the guages off I leaked some.
An indy shop already told me my compressor is bad and that the SAM is also faulty. (2400 total to fix)
I wish I asked them more about their diagnosis.
These pressure readings seem to indicate the same thing. If low is high and high is low.
I'll hook it up to my code reader when I get it in the mail.
Last edited by Onericali; Feb 14, 2011 at 08:39 PM.
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Thread Starter
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Joined: Aug 2010
Posts: 95
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2002 c230
Oh also, I seem to remember the AC taking longer to kick in, over a year before it went out completely.
What could cause this?
A gradual leak and failing of the compressor?
Could the SAM module that powers it gradually get worse? It doesn't sound like it right?
Which part of the compressor would have failed, or do I need a whole compressor possibly?
What else could give me these symptom
Low high pressure, Norm to High low pressure, and AC gradually taking longer to kick in?
What could cause this?
A gradual leak and failing of the compressor?
Could the SAM module that powers it gradually get worse? It doesn't sound like it right?
Which part of the compressor would have failed, or do I need a whole compressor possibly?
What else could give me these symptom
Low high pressure, Norm to High low pressure, and AC gradually taking longer to kick in?
Roger Wilco
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Member
Joined: Aug 2010
Posts: 95
Likes: 2
2002 c230
If it does not kick on, but the refrigerant level is fine, does that mean a bad compressor?
