Ac recharge. Gauge reads 0 pressure?

NjPrince · 05-17-2015, 01:18 PM

So ive done a regular ac recharge using a kit from autozone on my other cars but of course a bmw doesnt come without 200 more problems.

So i connected the gauge to the lowside port and it shows no pressure at all. The gauge is working because i connected it to my other car and it reads. Is it possible that there is no pressure?

My AC on the coldest setting blows out maybe 5 degrees less then room temperature. Basically room temperature. I figured I could get away with a simple kit but I guess the system has a leak?

markus037 · 05-17-2015, 03:49 PM

0 psi = no refrigerant. which means you have a leak somewhere. have someone re-charge it and add some dye to the system, run it and then look for where the dye is leaking from.

phubar · 05-17-2015, 04:18 PM

At this point if it's showing 0psi you might have to pull a vacuum in the system. You can do it all yourself with loaner tools from autozone.

ColoCoug · 05-17-2015, 05:48 PM

You also need to make sure that the new charge in the system has the appropriate amount of oil for lubrication. Finding the leak may be a job for an AC shop.

NjPrince · 05-17-2015, 08:32 PM

Thanks for the input people. Looks like this is more of a shops job. Def ganna be a leak somewhere

NjPrince · 06-02-2015, 02:47 PM

Quote:

Originally Posted by phubar

At this point if it's showing 0psi you might have to pull a vacuum in the system. You can do it all yourself with loaner tools from autozone.

Got quoted $600 for this job

Is there a DIY I can see to show me what you mean?

Sambonjo · 06-02-2015, 04:01 PM

I just had the same problem on my second car (09 Lancer). The shop recharged the AC and put in a sealant and dye in order to find the leak. That and a tire rebalance was $440 CDN. $600 USD seems really high.

BashShah · 06-03-2015, 03:18 AM

Just a thought.
The low side is on the drivers side near the shock tower right...
Second.
When I first got my BMW, coming from. An e46m3.... I noticed the ac was not blowing cold enough.
So I added more aC.....duhhhh.

More AC recharging made it worse.
Now no more cold air.

Took it to a professional shop and he looked up my car and said, you should have a total of 1.3 pounds.
I had 2.8.....shit.

As for your 0 psi..... See if it is true.
Push the low side OE high side connection with a pen.

The dye canister can be purchased from Walmart for like 15.

DN

phubar · 06-03-2015, 04:15 AM

Quote:

Originally Posted by Njprince0226

Got quoted $600 for this job

Is there a DIY I can see to show me what you mean?

google "a/c evacuation" for general DIY. Don't add any oil since you didn't replace anything. The auto parts store should be able to look up the amount of freon needed, try to get the cans without any oil in them (most 12oz r134 cans contain about 2oz of oil, a few contain dye as well) discount auto used to sell freon only cans.

critical05 · 06-03-2015, 07:52 AM

Its safest to have the system vacuumed so you know how much refrigerant your putting back in.

I found out the hard way on my truck. Figured it wasn't blowing cold enough and used a pressure gauge system to add more in. I ended up overcharging the system and blew out pressure relief on compressor. Wound up having to get a new compressor installed. Tried to save a few bucks but ended up paying more at the end.

shadow191 · 06-03-2015, 08:10 AM

If it's truly zero, then you have a pretty massive leak in the system. But I would make sure that it's not just a faulty gauge, the ones on those recharge kits are pretty bad. It may read on your other car, but maybe on the BMW, the pin isn't being depressed or something like that. I'd invest in a real gauge set from Harbor Freight, those read high and low sides, it's only $50 or so.

I'm assuming your AC is turned on. I would try again and see if it still reads zero. If it does, you can buy a dye kit from the parts store. I got one that was self contained like the recharge kits and pumped it in there. I immediately saw a massive leak from my condenser, replaced that and problem solved.

Most of the parts in the system are pretty easy to replace, the only exception is the evaporator. So if you do have a leak, pray it's not there.

And on modern cars, the compressor has safety cutoffs so it's very hard to damage it from overfilling. If you put too much refrigerant in, it cuts out when the pressure is too high to prevent damage. If there's not enough refrigerant, it also cuts out due to the low pressure.

05-17-2015, 01:18 PM	#1
NjPrince Captain 82 Rep 790 Posts Drives: 22' M3 Comp Join Date: Sep 2011 Location: NJ iTrader: (1)	Ac recharge. Gauge reads 0 pressure? So ive done a regular ac recharge using a kit from autozone on my other cars but of course a bmw doesnt come without 200 more problems. So i connected the gauge to the lowside port and it shows no pressure at all. The gauge is working because i connected it to my other car and it reads. Is it possible that there is no pressure? My AC on the coldest setting blows out maybe 5 degrees less then room temperature. Basically room temperature. I figured I could get away with a simple kit but I guess the system has a leak?
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05-17-2015, 03:49 PM	#2
markus037 Lieutenant 74 Rep 417 Posts Drives: Alpine White 2010 328Xi Join Date: Jan 2014 Location: Pottstown, PA iTrader: (0)	0 psi = no refrigerant. which means you have a leak somewhere. have someone re-charge it and add some dye to the system, run it and then look for where the dye is leaking from. __________________ ASE Master Certified PA Safety and Emissions inspector
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05-17-2015, 04:18 PM	#3
phubar Lieutenant 86 Rep 465 Posts Drives: 335 Vert Join Date: Apr 2013 Location: Fort Campbell KY iTrader: (8)	At this point if it's showing 0psi you might have to pull a vacuum in the system. You can do it all yourself with loaner tools from autozone.
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05-17-2015, 05:48 PM	#4
ColoCoug New Member 3 Rep 28 Posts Drives: 2008 E91 328xi Sportwagon Join Date: Feb 2015 Location: United States iTrader: (0)	You also need to make sure that the new charge in the system has the appropriate amount of oil for lubrication. Finding the leak may be a job for an AC shop.
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05-17-2015, 08:32 PM	#5
NjPrince Captain 82 Rep 790 Posts Drives: 22' M3 Comp Join Date: Sep 2011 Location: NJ iTrader: (1)	Thanks for the input people. Looks like this is more of a shops job. Def ganna be a leak somewhere
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06-02-2015, 04:01 PM	#7
Sambonjo Private First Class 20 Rep 115 Posts Drives: 2011 E90 335 Xdrive 6MT Join Date: Jan 2015 Location: Calgary iTrader: (0) Garage List 2011 BMW 335 Xdrive [0.00]	I just had the same problem on my second car (09 Lancer). The shop recharged the AC and put in a sealant and dye in order to find the leak. That and a tire rebalance was $440 CDN. $600 USD seems really high.
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06-03-2015, 03:18 AM	#8
BashShah Colonel 296 Rep 2,015 Posts Drives: 2012 335i Sedan Join Date: Oct 2012 Location: Vancouver, Canada iTrader: (0)	Just a thought. The low side is on the drivers side near the shock tower right... Second. When I first got my BMW, coming from. An e46m3.... I noticed the ac was not blowing cold enough. So I added more aC.....duhhhh. More AC recharging made it worse. Now no more cold air. Took it to a professional shop and he looked up my car and said, you should have a total of 1.3 pounds. I had 2.8.....shit. As for your 0 psi..... See if it is true. Push the low side OE high side connection with a pen. The dye canister can be purchased from Walmart for like 15. DN
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06-03-2015, 07:52 AM	#10
critical05 First Lieutenant 36 Rep 311 Posts Drives: E92 335xi 6 spd Join Date: May 2012 Location: IA iTrader: (0)	Its safest to have the system vacuumed so you know how much refrigerant your putting back in. I found out the hard way on my truck. Figured it wasn't blowing cold enough and used a pressure gauge system to add more in. I ended up overcharging the system and blew out pressure relief on compressor. Wound up having to get a new compressor installed. Tried to save a few bucks but ended up paying more at the end.
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06-03-2015, 08:10 AM	#11
shadow191 Lieutenant Colonel 181 Rep 1,681 Posts Drives: 2017 Volvo XC90 R-Design Join Date: Dec 2012 Location: GA iTrader: (3)	If it's truly zero, then you have a pretty massive leak in the system. But I would make sure that it's not just a faulty gauge, the ones on those recharge kits are pretty bad. It may read on your other car, but maybe on the BMW, the pin isn't being depressed or something like that. I'd invest in a real gauge set from Harbor Freight, those read high and low sides, it's only $50 or so. I'm assuming your AC is turned on. I would try again and see if it still reads zero. If it does, you can buy a dye kit from the parts store. I got one that was self contained like the recharge kits and pumped it in there. I immediately saw a massive leak from my condenser, replaced that and problem solved. Most of the parts in the system are pretty easy to replace, the only exception is the evaporator. So if you do have a leak, pray it's not there. And on modern cars, the compressor has safety cutoffs so it's very hard to damage it from overfilling. If you put too much refrigerant in, it cuts out when the pressure is too high to prevent damage. If there's not enough refrigerant, it also cuts out due to the low pressure.
	Appreciate 0 Quote