stargirl

hello,

apologies if i double post or otherwise brech forum etiquette, i assure you that its not intentional and is only a consequence of being unfamiliar.
my 2010 ML350 with 66K miles blows cold air when it is first started up. as i drive it gets warmer. the passenger side is cooler than the drivers side, until both sides get warm and they equalize. the longer the engine is off, the longer the cool air will last when its started up. after being off overnight, it cools for about 10 minutes. after a brief stop, it is less than a minute.
i live in south florida but drive about half the national average.
on 8/13 my mechanic said my lower side pressure was 55, and should have been 40. he added 3 oz of R134 on 8/13 and said i need a new compressor, receiver drier and evaporator expansion valve. total about $1700.
the additional freon didnt seem to make much difference. on monday i was on I-95 for 30 minutes and the car interior felt like about 100 degrees. it felt cooler outside.
my mechanic has always been honest and fair, but before biting the bullet i thought id ask forum experts for guidance.
from reading other posts, i see that having cooler air on the passenger side indicates low refrigerant. but we just added 3 ounces on 8/13.
does anyone have any thoughts?
thank you very much.

Maj. Dundee

With 66K I doubt seriously that you need a compressor. There is a leak somewhere and he failed to find it or he didn't bother to find it.

Did he use this similar machine to evacuate and recharge the system?

ItalianJoe1

If the low side pressure was too high, that's not indicative of an underfilled system. Either the compressor isn't pumping enough or the system is overcharged. What were the high side pressures? Need more info here.

If you have the clutchless compressor on your truck, it's very common for the refrigerant control valves to fail and not let the compressor pump properly, but they usually exhibit the opposite behavior, in that they don't cool at all and then suddenly start working normally.

stargirl

thank you maj dundee and italian joe1. !
maj dundee, unfortunately i didnt see what he used on 8/13 to check my system, but it took almost an hour. i will go back and hunt for a leak. a friend in IL said his mechanic put a dye in the freon and found his leak easily. that sounds hinky but i will ask about it.
italian joe1, MB medic. com said that MB started using clutchless compressors "on many late models" http://www.mercedesmedic.com/diagnos...mercedes-benz/
so i will ask what i have and also if he can also check the refrigerant control valve. will also ask about high side pressures.
will keep you posted when i know more---better yet when my AC is working again.
thank you again!

Maj. Dundee

Please UPDATE YOUR PROFILE in USER CP to include the year and 350 gas or diesel and where you live.

stargirl

update: after evacuating the system and refilling it with R134 and dye, no leak was found. but the compressor isnt compressing. it was about 90 degrees outside. the pressures were 60 low side (too high) , 130 high side (too low). so it looks like i will have to bite the bullet soon and have a new compressor installed. just in time for cooler weather down here LOL
thank you major dundee and italianjoe1!

Maj. Dundee

If you are going with a new compressor, get a Denso as they are the orig. equipment used by M/B. Recheck my findings to be sure.

https://www.densoproducts.com/Automo...sors-c247.aspx

stargirl

will do, maj.dundee. i see that you have a 2002 ML320. before this ML350 i had a 2000 ML430 for 11 years. the 350 is gorgeous and has every option known to man, but even after 5 years i dont feel comfortable driving it. never had that issue with the 430, which was also simpler to work on. thanks again for your input!

Maj. Dundee

The 2000-2005 MLs were the best SUVs

stargirl

any reason(s) aside from fewer electronics?

Maj. Dundee

If you really took care of it, the eng. and trans and transfer case were almost bullet proof.

stargirl

i do regular maintenance on my vehicles and treat them with respect. just looked at my old ML430 records and see that it also had a bunch of issues. so much for memory LOL

ItalianJoe1

The early ones were a bit before my time, but I feel like an early 166 with a 276 engine and steel suspension is almost bulletproof. I want to get one for the wife as a daily driver. Just a really solid, simple truck that I think will last forever, without being an old piece of junk.

Maj. Dundee

Very true.

Blesson Thomas

Hi

Have a AC problem with my 2007 ML350 W164..,The AC Clutch pulley hub is broken, do the centre shaft supposed to be spinning? shaft won't rotate at all.. just wondering when I applied so much force to rotate this 7mm bolt the shaft is not moving a bit even at all..is it in a locked position? or something wrong with the shaft as it is supposed to be spinning with Pulley? or the Pulley on bearing will spin and shaft just stay in position?

I have got a new front hub (clutch) kit...will this resolve the issue? or the hub will break as the shaft is locked (Pulley is rotating without any problem on bearing).?

It was blowing not too cold air in driver side before failing (seems leak) and auxiliary battery was down.

I apologies bothering you

Pls share if you got any video/info : blessxavi@gmail.com

Thank you very much

Blesson

Maj. Dundee

Blesson, stop opening multiple posts in the same forum. I already answered your question in the other post.

https://mbworld.org/forums/m-class-w...ml#post7689563

SXR

My 2013 ML350 blows hot air on the driver side and cold air on the passenger side, any ideas what the problem and solution would be?

Thanks

Maj. Dundee

You are on the wrong forum.

https://mbworld.org/forums/m-class-w166-149/