A/C low pressure point / A/C port locator

[Grail05]

very slow response in the maintenance section thought id post here to see if anyone knows where the A/C low pressure point is at... i know its close to the firewall but cant see anything there...

i have not turned on my ac for months and today its about 101 and turned the AC on and no cold air at all... my driver side blows outside ambient temp and passenger blows cold..

Yes both knobs are in the lowest setting possible 60... now im sure my evap is probably leaking but before i try that im just going to charge it to see if it will hold up... but i dont know where the low pressure recharge point.

[Grail05]

nobody? hmmmmm

[BMRLVR]

If the passenger side blows cold your evaporator is not leaking! The system only has one circuit so loss of refrigerant would mean no cold air on either side...... My guess is that one of the flaps are not working!

As for the low pressure charging port...... I think you may have to remove the rain-tray to access it!

[Grail05]

Originally Posted by BMRLVR

If the passenger side blows cold your evaporator is not leaking! The system only has one circuit so loss of refrigerant would mean no cold air on either side...... My guess is that one of the flaps are not working!

As for the low pressure charging port...... I think you may have to remove the rain-tray to access it!

hmmm now im confused on where to look at the flaps.. all the vents are blowing air assuming flaps are working? not sure if the flaps your talking about is the vents or somewhere inside and if it is i have no clue where it it.

ill check on that later. hope its not that hard to reach.

[bandit408]

The best way to check your AC is to hook up a set of gauges to your high and low side port and watch what the pressures are. The stuff they sell in the parts stores with only a low pressure gauge on will not tell you anything. This is one area it pays to have a technician that is good at AC to diagnose your car. It also saves time and money by using the correct tools. By the way never buy the freon with the stop leak in it. I have seen numerous times where it plugged up the orifice tube.

[SYZ]

Originally Posted by Sean05

hmmm now im confused on where to look at the flaps.. all the vents are blowing air assuming flaps are working? not sure if the flaps your talking about is the vents or somewhere inside and if it is i have no clue where it it.

ill check on that later. hope its not that hard to reach.

Flaps would be in the dash, yes? I imagine one of the flaps is not closing/diverting properly to direct the cold air through on the driver side. Could be a motor, could be a gear, could be a module. You might want to have a diagnostic test run on it so the issue can be pinpointed.

[VCMpower]

Your LP port is directly under the driver side cabin filter. You can reach it without removing anything. This does not sound like a refrigerant issue though. Have you pulled codes?

Originally Posted by Sean05

very slow response in the maintenance section thought id post here to see if anyone knows where the A/C low pressure point is at... i know its close to the firewall but cant see anything there...

i have not turned on my ac for months and today its about 101 and turned the AC on and no cold air at all... my driver side blows outside ambient temp and passenger blows cold..

Yes both knobs are in the lowest setting possible 60... now im sure my evap is probably leaking but before i try that im just going to charge it to see if it will hold up... but i dont know where the low pressure recharge point.

[epbb]

Originally Posted by Sean05

now im sure my evap is probably leaking but before i try that im just going to charge it to see if it will hold up... but i dont know where the low pressure recharge point.

Unless you are smelling the odor of cow manure, I can almost guarantee that your evaporator is not leaking (However, it should be noted though, that if your evaporator was leaking, you can still get cold air into the car). The odor of leaking Freon smells just like cow manure, so if it were leaking in the evaporator, it would be blowing into the cabin. I just went through a huge ordeal of having my evaporator replaced because it was actually leaking, and the odor was overpowering. I was still getting cold air in the car, but there was a very strong odor when it first kicked on.

There is a possibility that you could have a leak somewhere else, and it's not making its way into the car, but that's probably unlikely, since I would imagine you would still smell a slight odor.

I agree that it sounds like either one of the flaps in the blower housing, or somewhere else in the ducting, hasn't opened to allow for the air blowing over the evaporator coils (Which makes the air cold) to get to the driver's side air ducts.

[e92zero]

^i am assuming the smell of cow manure for the leak is when you turn ac on, correct? not when you turn off the ac.

[epbb]

Originally Posted by e92zero

^i am assuming the smell of cow manure for the leak is when you turn ac on, correct? not when you turn off the ac.

Exactly correct. However, if you leave it on for a while, the smell does eventually dissipate (Unless the nose just gets used to it). It would always come on very strong when the AC is first turned on.

[Grail05]

Originally Posted by VCMpower

Your LP port is directly under the driver side cabin filter. You can reach it without removing anything. This does not sound like a refrigerant issue though. Have you pulled codes?

never heard of AC pulling codes even with evap going bad..

looks like my evap is bad since i have been smelling cow manure for several months now .... have not used my ac for 3-4 months since it was not that hot until now.

[VCMpower]

correct equipment will pull codes on your HVAC system, ie servo motor, sensor faults ect. But it seems you have it figured out. Or sniffed it out

Originally Posted by Sean05

never heard of AC pulling codes even with evap going bad..

looks like my evap is bad since i have been smelling cow manure for several months now .... have not used my ac for 3-4 months since it was not that hot until now.

[Grail05]

Originally Posted by VCMpower

correct equipment will pull codes on your HVAC system, ie servo motor, sensor faults ect. But it seems you have it figured out. Or sniffed it out

oh wow didnt know...

Yea hate sniffing im just glad that i work 5 miles away and i get home within 10-15 minutes im just going to charge it and see if that give me sometime before changing the evap..sad thing is that its freakin expensive..

[VCMpower]

Check out Esquires engine pic in the Photos section and you can see the LP port. That will help you when feeling for it.

Originally Posted by Sean05

oh wow didnt know...

Yea hate sniffing im just glad that i work 5 miles away and i get home within 10-15 minutes im just going to charge it and see if that give me sometime before changing the evap..sad thing is that its freakin expensive..

[Grail05]

Originally Posted by VCMpower

Check out Esquires engine pic in the Photos section and you can see the LP port. That will help you when feeling for it.

found it..

[MilehighM3]

The passengers side can be cold/cool and the the drivers side warm due to the design of the evaporator. The refrigerant enters the evaporator on the passengers side and exits on the drivers side. The refrigerant evaporates as a result of low pressure due to an inadequate charge and the heat dissipation is complete at that time, resulting in a loss of cooling ability. Topping off the charge level with a proper evac and recharge will fix it short term, but once enough refrigerant is lost as a result of the leak the performance will diminish. Find a shop/dealer that is good at the job, don't go for the cheapest route. This is a major disassembly task that needs to be done properly!

[Grail05]

Originally Posted by Bmw135er

The passengers side can be cold/cool and the the drivers side warm due to the design of the evaporator. The refrigerant enters the evaporator on the passengers side and exits on the drivers side. The refrigerant evaporates as a result of low pressure due to an inadequate charge and the heat dissipation is complete at that time, resulting in a loss of cooling ability. Topping off the charge level with a proper evac and recharge will fix it short term, but once enough refrigerant is lost as a result of the leak the performance will diminish. Find a shop/dealer that is good at the job, don't go for the cheapest route. This is a major disassembly task that needs to be done properly!

Yea i hear you... and it cost $$$$$$$$$$$$$$ 2k give or take...

[MilehighM3]

Parts are about $500 and should be about 12 hours of labor, so yes unfortunately...

[VCMpower]

Originally Posted by Bmw135er

The passengers side can be cold/cool and the the drivers side warm due to the design of the evaporator. The refrigerant enters the evaporator on the passengers side and exits on the drivers side. The refrigerant evaporates as a result of low pressure due to an inadequate charge and the heat dissipation is complete at that time, resulting in a loss of cooling ability. Topping off the charge level with a proper evac and recharge will fix it short term, but once enough refrigerant is lost as a result of the leak the performance will diminish. Find a shop/dealer that is good at the job, don't go for the cheapest route. This is a major disassembly task that needs to be done properly!

Good breakdown

[Grail05]

Originally Posted by Bmw135er

Parts are about $500 and should be about 12 hours of labor, so yes unfortunately...

hmmm not sure if i have the energy to do this myself. taking of the dash sure will be a PITA... i know its not worth the time and saving the extra not sure if its worth it...

but just for experience might do it.. ive taken dash off the car before and yes even on a honda is a PITA... hmmm something to think about..

[M3amigos]

I just had my AC issues resolved. I hadn't really noticed the issue until it started getting warmer out. Driver side was much warmer than the passenger side, and on hotter days it would just blow warm air on both sides. I took it in to the dealer and they found the freon to be 14oz low. They did a nitrogen pressure test, after 20 mins they saw a pressure drop then traced the leak to the evaporator. With two technicians they pulled the dash, swapped it out, and had the car ready for me in just 6 hours. Everything went back together perfectly, no rattles or anything. My CPO warranty covered all the costs, aside from a $50 deductible. The SA advised it would have been roughly $2300 job otherwise. AC is now working better than ever, comes on ice cold very quickly and I have to bump it up to 75 to keep it from freezing me out. Definitely a happy camper with the florida summer coming!

[Grail05]

Glad it worked out for you... im SOL will be doing this myself.

Stupid BMW A/C designer

Originally Posted by M3amigos

I just had my AC issues resolved. I hadn't really noticed the issue until it started getting warmer out. Driver side was much warmer than the passenger side, and on hotter days it would just blow warm air on both sides. I took it in to the dealer and they found the freon to be 14oz low. They did a nitrogen pressure test, after 20 mins they saw a pressure drop then traced the leak to the evaporator. With two technicians they pulled the dash, swapped it out, and had the car ready for me in just 6 hours. Everything went back together perfectly, no rattles or anything. My CPO warranty covered all the costs, aside from a $50 deductible. The SA advised it would have been roughly $2300 job otherwise. AC is now working better than ever, comes on ice cold very quickly and I have to bump it up to 75 to keep it from freezing me out. Definitely a happy camper with the florida summer coming!