A/C compressor "pulsing" and nearly stalling my engine at idle

That IS cold. What can you do if it's working? As long as it works turn it on lol.

 

Now that you told me to keep an eye on that fan, I have read around where that same fan issue has destroyed the entire a/c setup, by failing and causing a domino effect of failures throughout the system.

So, even though the a/c seems to be working well, I will keep an eye on that fan.

 

So, if the pressure is within specs on the low end, where I put the freon in, is the entire system at safe pressure?

Being as cold as it is, i worry about it being overcharged.

It doesn't surge when the compressor kicks on, as I have seen overcharged compressors do in the past.

 

My readings when I filled it to specs once (I had to do a heater core) showed 38 low side and around 350 0n the high side.
My fan has craped out twice and it didn't affect the rest of the system. I didn't run it tho. Once I noticed the AC wasn't cold I check to see what's going on and stop using it till I replace the fan.
You could have too much freon, I really don't know. If you have no leaks and you add then of course you have too much. Have you put guages on it?

 

35 on low side, currently. I assume I have a slow leak, since I have to add a can at the beginning of every summer for the past 2 years.

 

Low freon condition also makes the compressor cycle more. It pumps the freon into the high side leaving the low side low causing the low pressure switch to shut the comp off.
I'm sure you know that it's best to use real guages to see both sides and that you should find that leak. Could be a simple "O" ring somewhere. Could at least check all the visible connections for oily residue. Also look at the compressor case real close. If you suspect something, use soapy water and see if it bubbles up.

 

I may drive it through one of those "Free A/C check" places. They will OF COURSE find a problem so they can charge me an exhorbitant amount to fix it...

I don't have the professional gauges. Just the one that comes with the gun to add freon, and it is a cheapo walmart special.

 

Just an update...Blugene was right. It was the electric fan behind the condenser.

 

Now I wonder how much freon is in the system. .. I suppose if it's working it's ok. Glad I could help.

 

dude, i work for dodge... you literally wouldnt believe how many ive changed!!!!! even worse are pt's probably one or two a week i see same complaint, engine runs rough at red lights and ac not blowing cold. same crap everytime low speed circuit in the cooling fan pooped.

 

It has worked great after swapping the fan (and a personal phone call to blugene!!! Which helped me fix it.) Then a light extra charge.

 

I learned some new stuff about our trucks today.
Not sure about your transmission but mine has 2 filters.

 

Yep, 2 filters. A flat one like most cars, and a screw-on one that looks like an oil filter.

That is one job I let the shop do. I hate cleaning up trans fluid.

That and swap spark plugs. The hemi has 16 of them, and 14 of them are nearly impossible to reach.

I pay someone else to cheese-grate their arms...

 

Now you tell me

 

oughta tune up a durango with a hemi!