R134 capacity ?

[terra]

You can go either way, I have used the cans before with good results but they are finicky sometimes. The first time I did it with great results. There is a very tiny leak so I had to charge again and it didn't work as well the second time, I added some oil too and a full can of refrigerant and still wasn't very cool. At this point I had lost track completely of what was in the system and the pressure was high so I stopped and had it professionally recharged the other day.
It had .5lbs in it when the charge started (wasn't really blowing cold at this point) and machine emptied, did a leak test (non detected apparently) and charged with 1.6lbs. Blows very nice now
Honestly, if the leak is very slow (or you have lost track of the amount of R134 in it), a professional charge is the way to go.

It's not too hard to fill by mass yourself, even if using small cans Draw a full vacuum on the system. Disconnect pump. Turn on car

Weigh a can. Hook it up to your system, purge the lines, open the valves, let it fill until the can is empty. Close valve. Weigh can off the car. Difference is how much refrigerant entered the system. Should be very close to the listed weight on the can. Fill up another can that way. Last can will need to be a partial fill. If you have a scale that can measure accurately live you can just watch until the number matches the amount of refrigerant you need to fill. Otherwise just keep connecting / disconnecting until you hit your desired mass. Tolerance is something like +/- 40g, so you do have some room. Write down how much is left on the can so that you can use it next time.

That will have the AC blowing quite cold until it leaks out again. Replacing the schrader valves on my car significantly slowed my leak, but it's not gone. I suspect I have an evap leak like most of these cars develop. And that's a bitch to replace.

Only issue is if your AC is not completely empty, drawing the vacuum will vent refrigerant to the atmosphere. Which is not very nice for the environment. Though I suppose if we all have leaks, it'll all end up in the atmosphere eventually anyway.

[SliM3]

Thanks for posting this! I need to recharge mine and will be using a DIY kit from Amazon, but couldn't find these numbers anywhere!!

[Maxima SE]

you guys all have great points ! but the point of this thread was to try and verify if the capacities I posted are correct with the goal of me making a DIY when i do this on my 2005. People in the future can decide for themselves if they want to attempt this on their own or leave it to a professional.

With that said, can some of you verify the above capacities I posted with the sticker under your hood?

[terra]

[Maxima SE]

thank you, what year?

[BearDeXPS]

I always thought when there's an obvious delta between vents the issue is with the resistor... not levels

https://www.ecstuning.com/b-genuine-...r/64116923204/

[terra]

thank you, what year?

05. I don’t think there’s a true difference year to year

[Tbonem3]

I always thought when there's an obvious delta between vents the issue is with the resistor... not levels

https://www.ecstuning.com/b-genuine-...r/64116923204/

Not so much in the e46, but in my e36, it happened like clockwork. The right vents would stop being cold. I'd recharge it, they'd be cold for the rest of the year. Then the next year, same thing again. Never touched the resistor or any other part of the system.

[Pnick]

Not so much in the e46, but in my e36, it happened like clockwork. The right vents would stop being cold. I'd recharge it, they'd be cold for the rest of the year. Then the next year, same thing again. Never touched the resistor or any other part of the system.

Same exact experience here also...

[terra]

Anyone ever try this stuff? http://www.cryochem.com/r134a.php

I know general rule is that stop-leak = bad. But at least on Mercedes forums they seem to swear by that particular stuff. Problem is they won't sell to DIYers without various licenses and wahtnot. Might be worth considering the gamble given how much of a pain it is to actually replace the evaporator. At that point it wouldn't cost *that* much more to replace the compressor, condensor, and all the lines.

[George Hill]

I would like to evacuate and refill my refrigerant. I vaguely remember from M3F that the capacity was different for the E46 M3 throughout the production years. Unfortunately I do not have the luxury of looking under the hood for the sticker as my car came with a vorsteiner hood and the sticker is no longer there. Is there any way to verify the capacity by VIN or other information? Can anyone with a 2005 tell me what their fill capacity is?

Every E46 I have seen is 1.63lbs R134a. There may be differences for the Non-US 4cyl and diesel cars but I can't say for sure off the top of my head.

[George Hill]

I may make a separate thread on this if I don’t see a response. I have noticed that I get semi cold air blowing out on driver side, but lukewarm-warm air on passenger side when driving. Do I just need a recharge or is something more going on?

edit: spoke to a friend who was a BMW tech for a while, pretty classic BMW symptom of needing a recharge.

The refrigerant enters the evaporator from the drivers side and continues to the passenger side. If the freon levels are lower than spec the system is not able to cool the entire evaporator thus you get hot air from the passenger side of the evaporator first (as it is further from the inlet/expansion valve). In Texas 99% of the E46 low refrigerant issues I see are evaporator leaks. Sometimes you'll get a schrader valve leak and same from the compressor, but relatively uncommon in my experience. To diagnose this I evacuate the system and if there is 0.3-0.4lbs refrigerant than it's most likely an evaporator leak, (for some reason they won't leak completely empty). From there I'll then pull the microfilter housing and remove the blower motor cover. Look in past the blower motor and you can see the evaporator. If it has a buildup of grime then that is usually the point of leakage, sometimes its in the corners but usually it builds up in the middle.






IF the leak is really big then you can add dye to the system and if you do that once or twice you can sometimes get dye out of the evaporator condensation drain. I usually see this with E9x and E7x cars but it will do it on E46s if the leak is large.

[Inizes]

The refrigerant enters the evaporator from the drivers side and continues to the passenger side. If the freon levels are lower than spec the system is not able to cool the entire evaporator thus you get hot air from the passenger side of the evaporator first (as it is further from the inlet/expansion valve). In Texas 99% of the E46 low refrigerant issues I see are evaporator leaks. Sometimes you'll get a schrader valve leak and same from the compressor, but relatively uncommon in my experience. To diagnose this I evacuate the system and if there is 0.3-0.4lbs refrigerant than it's most likely an evaporator leak, (for some reason they won't leak completely empty). From there I'll then pull the microfilter housing and remove the blower motor cover. Look in past the blower motor and you can see the evaporator. If it has a buildup of grime then that is usually the point of leakage, sometimes its in the corners but usually it builds up in the middle.






IF the leak is really big then you can add dye to the system and if you do that once or twice you can sometimes get dye out of the evaporator condensation drain. I usually see this with E9x and E7x cars but it will do it on E46s if the leak is large.

I’ll go take a look sometime today. I sure hope it’s not the core cause that’s a pain in the ass to replace...