A/C not blowing cold

Flying_NEB · Post by **Flying_NEB** » Sat May 17, 2008 9:12 pm

My car's got 150K on it (just hit that on Friday!). Today was 88 degrees and I wanted some A/C - but it barely got cool. who thinkis it just needs a recharge?

Who thinks it's probably something more?

alsey_seven · Post by **alsey_seven** » Sat May 17, 2008 9:16 pm

its something else i have 169,000 and its cold

Paul56 · Post by **Paul56** » Sat May 17, 2008 9:51 pm

If it does need a recharge then it has a leak.

Might be a good idea to get the leak if any fixed first then do the recharge... that is if there is a leak.

Moparty08 · Post by **Moparty08** » Sun May 18, 2008 1:23 am

Mine is charged but does not blow cold air. What could this be? is it a bad compressor? I'd love to know cause i can stand cold weather but can't stand heat and it's getting pretty damn hot.

BlackRoseRacing · Post by **BlackRoseRacing** » Sun May 18, 2008 7:34 am

Who charged it?
Have a shop pull a vacuum on the system to check for leaks, then have them recharge it...

BRAD727 · Post by **BRAD727** » Mon May 19, 2008 10:53 pm

i use to work at a shop and u need to charge it. but cars that are kinda old shouldnt waste the money because most likly it wont work.

Flying_NEB · Post by **Flying_NEB** » Sat May 24, 2008 7:07 pm

my heater wasn't blowing hot either. I was reading in my haynes manual and it seemed to say that if the a/c aint cold and the heater aint hot, it could be a water pump problem. I bought this car with 133K miles on it and I have no idea if the water pump was ever changed. So, I'm gonna take it in next week and have them check everything out and give me their thoughts.

Post by **occasional demons** » Sat May 24, 2008 8:15 pm

Your water pump has nothing to do with your A/C. Check your coolant level, if it is low the coolant won't get to the heater core, so there will be little heat. IIRC there is an air blend door inside the HVAC unit it may be stuck inbetween the hot and cold, degrading the performance of both systems.

mopardave913 · Post by **mopardave913** » Sat May 24, 2008 11:24 pm

easy fix here. Resistor pack behind glove box, mounted against fire wall. Those go bad in jeeps, chrysler and dodge mini vans, and neons. I would say that is the problem, on of the common signs is the air isnt cold anymore or the fan doesnt work on 1 or 2, but it works on 3 or4.

Flying_NEB · Post by **Flying_NEB** » Sun May 25, 2008 12:58 am

the fan works great all the time...I'll check some things out and let everyone know what fixes it.

Adionik · Post by **Adionik** » Sun May 25, 2008 12:59 am

Mine did this after a UDP

gilly02le · Post by **gilly02le** » Sun May 25, 2008 10:22 am

^^^ I dunno man, but my car has a udp, and still has ridiculously cold A/c.. i can't even use it on full usually since its uncomfortably cold. And thats with 125,000km on my car.

Post by **jonnymopar** » Sun May 25, 2008 11:11 am

92k here, UDP installed for nearly all of that, and my A/C kicks ass.

kc2005ptgt · Post by **kc2005ptgt** » Mon May 26, 2008 1:45 am

I would say to check for leaks, coolant, and find out from whoever you got it from if they ever changed the water pump, timing belt, etc... may need all that stuff as well, anyway.

01NeonSnooZer · Post by **01NeonSnooZer** » Mon May 26, 2008 9:27 am

Okay guys, go with the easiest to check, first.

Change from dash to floor to defrost. Change it from A/C to heat. This will make sure everything in the blower case is working porperly. You've already established that the blower motor works properly so that's out.

Next, with the engine running, inspect the A/C compressor clutch. Look to see if its working and look for reddish colored powder on/around the compressor/compressor area. That's a sure sign the compressor clutch is slipping or not grabbing at all. If you can SEE that the clutch isn't grabbing at all, the pulley will freewheel and the clutch itself will remain still. This means that for whatever reason, there's no power or ground for the compressor clutch. Check the relay in the underhood fuse panel. If you have to, gently (and I emphasize this because you can easily damage the inner workings of the relay if you just pry on it willy-nilly) remove the black case from the relay to expose the relay's innards and check for corrosion. Power up the relay and make sure it actually clicks. If it works, then move on the the wiring harness to the clutch ( usually 3 wires-power, signal, ground). make sure there's no chafing/rubbing of the harness. Check the wires themselves to make sure they're not melted together or broken.

If he clutch is coming on and not slipping, check to see how often it's engaging. If not often enough, it could be a bad pressure sensor. If too often, it could be the same or, more likely, the system is low on charge. If this is the case, take it to a tech you trust (or dealer you trust), have them hook up a recovery machine and pull a vacuum. If the system will not hold vacuum, it has a leak. At which point, the tech can put in a test charge and use a light that looks like it was stolen from the set of CSI to diag a leak. It's a UV or blacklight. The refrigerant will glow under UV or blacklight. If you feel just so inclined, the blacklight thing is something you can probably do at home.

I'm sure there's other options but I can't think of them right now but this should be a good place to start.

Moparty08 · Post by **Moparty08** » Mon May 26, 2008 11:19 pm

sweet. there's a place in my town that does free ac checks so i'm gonna go there to check into it. today i was moving things from my basement into storage and it being 90 out ac was definitely nice in the suv i was in.

01NeonSnooZer · Post by **01NeonSnooZer** » Tue May 27, 2008 1:46 pm

Let us know what the A/C check yields.

Flying_NEB · Post by **Flying_NEB** » Tue Jun 03, 2008 12:48 am

Okay, so I didn't take it to a shop yet, but I did get the A/C recharge kit. I got the hose out and checked the levels - I was in the Red Alert level which means "go to a professional, the problem is not an a/c charging issue".

So, do you have thoughts other than "take it in to a shop"?

As a side note, I did check the coolant levels and they're fine. Also, I replaced the radiator in February because the old one was...well...getting old and I thought it might help my heating issue. Along with that I replaced the thermostat and upper/lower hoses. Is it possible I missed a connection somewhere to the a/c condensor? I looked around but didn't see anything standing out.

zinalco · Post by **zinalco** » Tue Jun 03, 2008 3:28 am

I have been about 3 months without a/c it started to fail blowing fuses when turned on whe the A/C clutch kicked in it did it very often and just changed the fuses and then it just stoped working without blowing fuses any idea?

01NeonSnooZer · Post by **01NeonSnooZer** » Tue Jun 03, 2008 10:26 pm

zinalco wrote:I have been about 3 months without a/c it started to fail blowing fuses when turned on whe the A/C clutch kicked in it did it very often and just changed the fuses and then it just stoped working without blowing fuses any idea?

Check for chafed wires. Sounds like a short to power before the load or a cross short. Those usually will blow fuses.

Flying_NEB wrote:Okay, so I didn't take it to a shop yet, but I did get the A/C recharge kit. I got the hose out and checked the levels - I was in the Red Alert level which means "go to a professional, the problem is not an a/c charging issue".

So, do you have thoughts other than "take it in to a shop"?

As a side note, I did check the coolant levels and they're fine. Also, I replaced the radiator in February because the old one was...well...getting old and I thought it might help my heating issue. Along with that I replaced the thermostat and upper/lower hoses. Is it possible I missed a connection somewhere to the a/c condensor? I looked around but didn't see anything standing out.

First thing, please read both of my posts all the way through. If you're patient, you might find something that will help you.

It actually could be an A/C charging issue. Too much refrigerant brings the pressure too high. Due the the pressure/temperature relatioship with both R12 and R134a, the higher the pressure, the higher the refrigerant tmperature and because heat travels from hot to cold, the fact that the refrigerant temperature is too high (due to the excessive pressure), the ambient heat in the passenger compartment cannot be transferred into the evaporator and, in turn, to the refrigerant and then passed out the the outside air via the condenser and so the air will blow warm out of the vents.

In lamen's terms, too much refrigerant can make th A/C blow hot.

The other possible cause is that the TXV (Thermostatic Expansion Valve) on the firewall may be inop, possibly stuck closed. If this is the case, the high pressure side will read too high and the low pressure side will read to low. It the valve is inop stcuk open, you'll have (I think) a low high side pressure and a high low side pressure. The latter doesn't sound like what you've got. Go to the A/C shop and have them hook up a set of manifold guages. It'll tell you exactly what's going on for the most part.

EDIT: I asked one of the other techs in the shop if my "Low High, High Low" is correct and he said it was. I trust him, he's been in the business since before I was born.

And you could be right about missing a connection. If the pressure sensor on the Reviever/Drier (Accumulator) is not plugged in, you could see some issues but it still sounds to me like you have an overcharging issue.

Now, usualy, there will be a black sticker under the hood somewhere that will show at least the oil and refirgerant charge amount. Sometimes it will also show the belt routing on it, as well.

Now you haven't said that your car is over heating at all but if it is/does, depending on the car (I'm not sure if the Neons do it but my old '93 5th Avenue and '91 New Yorker did this), when it overheats, the condenser being so close to the radiator can cause the condesner to heat soak and not cool the refrigerant and it'l make your A/C blow warm.

The thing I would check first is the state of charge. Again, if you have a high side pressure that is to high and a low side pressure that is too high, you're over charged on refrigerant and you may simply need to have the refrigerant recovered, a vacuum pulled and then the proper amount of refrigerant and oil installed. Now if your sticker is gone, you may have to go to the dealership and have them look up the proper amount of oil and refrigerant. You may not have to do that, though. I will look it up in Mitchell On-Demand tomorrow and see if it has the oil and refrigerant capacities listed for the PL Neons if I can remember to do so. If it's listed, I will post it here as a reference for you to take to the A/C shop for their checkup. There really is no way for you to check ho many Lbs of refrigerant is in your system at home unless you have access to a recovery machine. The reason for this is that the recovery machine has a built in scale that the tank sits on and is usually very accurate and can tell you to the 1/100th of an ounce. Your set of manifold gauges cannot tel you how much refrigerant is in the system.

Flying_NEB · Post by **Flying_NEB** » Wed Jun 04, 2008 2:07 am

I have not had any overheating issues.

As far as the a/c clutch, how can I tell if it's kicking in. I think I know what/where it is, but I can't exactly see the inside. All the belts that I can see are moving and when the a/c is on you can feel the slight power loss (which I've had on any car I've owned).

As far as the pressure goes, I checked the low side (that's what the instructions said) and if I'm correct in figuring out what the high side is, my gauge doesn't fit on that spout.

I understand what you mean about too much pressure making hot air (same principle as a cold air intake).

Thanks for the info.

Post by **occasional demons** » Wed Jun 04, 2008 9:33 am

Your radiator fan should kick on within a few seconds of your A/C clutch. (unless ambient temp is extremely cold) the older systems kicked it simutaneously with the clutch, but the newer ones depend on condenser temp/pressure, not sure which - prolly pressure. Turn the a/c on and watch the compressor (under the PS pump) to see if it cycles. The center part of the pulley will start and stop. IIRC if either the high or low pressure switch doesn't see the correct value, or they have failed, (common my brother's van has gone through 3) then the a/c clutch will not kick on. But you will have to take it to a shop to have any parts replaced, other than the a/c clutch coil, and that may be a PITA to do on the car.

01NeonSnooZer · Post by **01NeonSnooZer** » Wed Jun 04, 2008 11:23 am

Couldn't have said it better.

Post by **occasional demons** » Wed Jun 04, 2008 12:24 pm

After that last post your fingers prolly needed a break!

01NeonSnooZer · Post by **01NeonSnooZer** » Wed Jun 04, 2008 12:54 pm

He's sayin his low side pressure is in the red, tho! Holy crap. I mean if it was a bit high, you could hook up the mani-guages and see if the high side is low. This would be a compressor cycling issue but with the low side being that excessive, I'm inclined to think it's overcharged.

I went on Dealer Connect today and got the specs for the A/C oil and refrigerant charge amounts. This is a little bit to remember but if you give you VIN# to the dealer, they should be able to tell you for free if you've had the TSB done.

Refrigerant capacity is 1.69lbs if build date is before 07/01 or if TSB# 24-23-99 has NOT been performed.
Refrigerant capacity is 1.875lbs if build date is after 07/01 or if TSB# 24-23-99 HAS been performed.

A/C System requires ND-8 PAG oil. Capacity is 6.10 ounces, regardless of build date or TSB.

01NeonSnooZer · Post by **01NeonSnooZer** » Wed Jun 04, 2008 1:14 pm

Flying_NEB wrote:I have not had any overheating issues.

As far as the a/c clutch, how can I tell if it's kicking in. I think I know what/where it is, but I can't exactly see the inside. All the belts that I can see are moving and when the a/c is on you can feel the slight power loss (which I've had on any car I've owned).

As far as the pressure goes, I checked the low side (that's what the instructions said) and if I'm correct in figuring out what the high side is, my gauge doesn't fit on that spout.

I understand what you mean about too much pressure making hot air (same principle as a cold air intake).

Thanks for the info.

It's not so much like a cold air intake as it as a turbo. When you compress the intake charge (Boost), you heat it up. Hence the need for an IC. Same thing with the refrigerant.

Flying_NEB · Post by **Flying_NEB** » Wed Jun 04, 2008 3:40 pm

(got ya on the cold air vs turbo)

The fans have been kicking on and whatnot.

Anyway, I took it in today and they'll call me after they diagonose. I'll let ya know what it is.

01NeonSnooZer · Post by **01NeonSnooZer** » Wed Jun 04, 2008 5:51 pm

allrighty.

Hey, on a little side note, how far up does your little guage go that you used to measure the low side pressure?

Flying_NEB · Post by **Flying_NEB** » Wed Jun 04, 2008 7:20 pm

I'll have to check it - but I vaguely remember the "normal" range being in the 45 area and yellow was like 65 and red was 75+ . . . but I'll double check it.

The shop said apparently a wire going to my ac clutch was damaged or something an the wire had to be repaired or something. So they're doing that as we speak (or I type, whatever) and then they're going to check it again to make sure that worked.

01NeonSnooZer · Post by **01NeonSnooZer** » Wed Jun 04, 2008 7:33 pm

You could have checked that in your driveway. You didn't have to spend money on it. But hey, easy fix so you'll have it back soon.

But I bet that guage you got in that recharge kit is inaccurate. Did the tech or service advisor where you took your car say anything about the state of charge? I bet if he were to hook up a good set of manifold guages or a recovery machine, he'd find the pressures normal. Being that the wiring harness was damaged, I would venture a guess that the compressor clutch wasn't engaging.

2GN.ORG

A/C not blowing cold

A/C not blowing cold

i also have a a/&c problem

Re: i also have a a/&c problem