mbb3303

When I first start my 2011 Civic it blows perfectly strong and cold. After about 5-10 minutes of driving the force of the air coming through the vent basically goes down to nothing (although what little is still coming out is still cold). If I turn the AC off completely while driving once it has stopped and wait for 5 minutes it again blows at full force but then again goes down to barely anything shortly there after. My AC compressor was recently replaced, which wasn't cheap. So the fact that this is still a problem is disconcerting, especially with the hot Texas summer approaching quickly. Any thoughts on what this may be?

ezone

Evaporator core is freezing solid.

The system is supposed to cycle the compressor off about 35*F so the core doesn't freeze, then turn the compressor on about 38*. Repeat (cycle) to keep the core temp in this narrow temperature range just above freezing.

(vent temp can be much higher than the core temp)

You need to figure out why it's cycling at too cold a temp or not cycling at all.

So...does the compressor run continuously, or does it cycle long after the core is too cold?

mbb3303

When the air starts to blow weakly even when it's at its highest speed I can hear the fan blowing at full force. Just nothing is coming out. Does that answer your question?

ezone

No, the fan is supposed to run all the time
The AC compressor is bolted to the engine. It makes that loud CLICK when you turn on the AC.




Do you have to jump start the car?
Does it act like it has a weak battery after sitting overnight? (cranks slow)
Has it ever burped out a cloud of stink from the engine compartment while sitting still with the engine running?

If so, it might have the clutch relay stuck on.

mbb3303

Car starts fine and doesn't seem weak after it's been sitting.
No noticeable smell in the cabin. However, on occasion, something that looks like white smoke (has no smell) will come through the AC vents.

ezone

That would be the same thing as fog, it can be normal especially if you don't have the system set on recirculate.




Can you tell (visually discern) when the compressor clutch is engaged and the compressor is running?
Now, can you tell the same thing----is it still running when it shouldn't be?
Do the radiator fans turn off but the compressor keeps running?

If the compressor is running while it shouldn't be, then tap on the clutch relay. If it turns off, the relay is the cause.

ezone

Compressor relay is #1 in this diagram (I know it says CRV, it uses the same box):

ezone

Basically you need to figure out why the compressor isn't turning off at the correct (evaporator core) temperature:

Does the compressor cycle off too late (cold) and the evap core is freezing because of it?
Is the compressor staying on because the control panel is faulty?
Is the compressor staying on because of a clutch relay fault? (the most common problem, many times this leads to a dead battery after sitting overnight)

mbb3303

This is great info and I greatly appreciate you taking the time of pointing me in the right direction. I am taking my car in on Thursday back to the same guy who put in the new compressor. This is the 4th time I will be taking it back to this mechanic. He's proven to be less than competent. Originally the quote to replace the whole system was $1900. I thought this was steep and opted to go the cheaper route with this guy. I guess you get what you pay for. Soon as I find out the cause I will reply to thread.

Thanks again for your time on this Memorial Day.

ezone

Mechanic is broken. Replace mechanic.

Seriously..... Did he replace the compressor for this same exact problem?

mbb3303

No, it originally wasn't blowing cold anymore. He put on a used part. Then it broke. Then I brought it back and he put in a new compressor. Then he forgot to mount the compressor. So it broke the belt when I attempted to drive it. And I brought it back again and he fixed the belt and mounted it correctly like you should've in the first place. Now this problem. Luckily I am only invested about $400 worth because he hasn't really charge me any more money when I have brought it back. I know I need to take it somewhere else. But I kind of want this guy to get it right so I don't have to pay anymore money.

ezone

Do you trust this person with something more complicated than a light bulb replacement?