1995 Quest A/C Problem

[skukreja]

Hi All,

I am new to this group, so want to say that if the question sounds silly then please excuse me.

I have a 95 quest whose A/c went out in phases. First the front A/C stopped cooling but the rear was fine. Then the rear also went out.

I had the van checked and they found no leaks but no Freon either. So somehow the freon got out. So I brought a charge kit and charged it to the pressure that is recommended (45 PSI). The rear A/c cools but not up to the expected level. The front still does not. So I decided to check it out. I find that when I turn on the A/C in the front, the metal tubing that comes into the evap cools nicely but then shuts off after a minute. The rear one does not. This led me to believe that the thermostat in the front is doing this since the blower works fine. I cannot find where the thermostat is for the front A/C. I also need to know how to determine if it is working or not.

Please help.

[psmith22]

skukreja;

My 1995 Quest had the exact same problem.

The bottom line was a blocked orifice in the liquid line.

It's a long story, but after my battle, I feel I have to tell it.

The car had worked flawlessly up until this year, when the air conditioner just quit cooling. I bought a Haynes repair manual, searched the web and talked to at least 10 mechanics. All said the same thing: Take it to a repair shop.

I did. After a $2,175.00 estimate to replace, the rear evaporator, all manifold lines, accumulator, compressor and radiator fan, I decided to tackle it myself no matter what the outcome.

Initially, when the unit stopped cooling, I started by trying to add R134.
No matter what guages I used, they showed pressures way to high! (thats when I bought the manual and started talking to mechanics) All sources pointed to a blockage in the system. When the repair shop told me it was empty and they charged me $384 to evacuate, refill and estimate. I proceeded to tear the entire system apart.

This is not easy. I don't reccommend it. I already have. The end result was a clogged orifice tube, located in the liquid line that runs from the condenser to a "T" fitting and then straight into the evaporator in the firewall. the other side of the "T" goes to the rear evaporator, where the orifice tube is contained in the the elbow connecting the manifold lines to the rear evaporator, under the car.

I replaced this line,(it comes with a new orifice) about $60, and a new accumulator, had the system evacuated and proceeded to reinstall 52(not 48) ounces of R134, and oil. Keep in mind that after evacuation, you will have to jumper the low pressure switch on the accumulator to get the compressor to run, until there is a sufficient amount of R134 in the system to keep it closed. By the way, the compressor made unusually loud noise until there was about 30 ounces of R134 in the system.

After about 40 ounces of R134, the rear unit started cooling first. It will do this as it has a Chrysler "H" style expansion block at the evaporator. At about 48 ounces the front system started cooling. With a full 52 ounces, the entire systems started working again.

In 100 degree weather(north Texas) at idle the front unit will produce 48 degree air at the vents. In city driving, about 42 degree air, and on the highway, after a couple of minutes of driving, right down to 33 degrees. the rear unit produces slightly higher temps but not by much.

Keep in mind, that it requires a special tool to take all the manifold lines apart and access to them in the engine compartement is down right insane, not to mention nuckle busting. Access to the rear requires you to safely jack up the car, and dissassemble the entire driver side interior. and working with high pressure lines is inherently dangerous, so use all precautions.

the real question to ask: Is it worth it? Our Quest has 170,000 miles on it, has had consistent and regular maintenance and still runs great. With a new lease on life for the air conditioning, were going to try and get a few more years out of it.

Good luck.

Phil Smith

[LWild]

I have a 1996 Quest van and have chronic problems with the A/C. I live in Phoenix, AZ and it seems the Quest A/C compressor is designed to shut down when it gets too hot. In practice, that means when the outside temperature gets over 105 or so that the compressor shuts off whenever you stop at a light. I comes back on once you start driving again, but when driving in the city, this isn't enough to keep the vehicle cool. It's not a whole lot better than driving with the windows open. The dealer replaced the compressor 3 times under warranty before telling us they had received a notice on the problem and installed an additional part. After they did this, it didn't shut off at lights anymore, but it didn't cool as well the rest of the time either. That compressor lasted about year with the modification and then went out. By this time it was out of warranty and we replaced the compressor at our own expense - and didn't put the extra part on (whatever it was). We're about 6 months out from this repair.

We also had a bolt break off and fall down into the engine at about 102,000 miles (we had the 100,000 mile service plan). Our options were, take the bolt out, hope for the best and sell to some unsuspecting person ($500) do a larger repair ($3,000 - I don't remember the details) or put a remanufactured engine in ($4,000). We went with the remanufactured engine because it came with a 3 year warranty and the other fixes only came with 30-90 day warranties.

Now (130,00 miles) we are having transmission problems and have been quoted $2,700 to fix those.

We have been meticulous with maintenance and care of this van and it's never been in an accident. One of our neighbors had a 1993 Quest and has had some of the same problems, so at least the A/C and the bolt issue appear to be design flaws. Knowing what I know now, I would have gotten rid of this van as soon as the warranty expired.

['90 Escort Man]

After searching 13 pages in Villager, and 8 in Quest, psmith22 has the closest to my problem, but request any and all to assist me.

I have 2001 Villager, front air blowing warm. Underdash controls work appropriately, along with temp control. Saw them physically move. Rear air works great. Compressor cycles on/off every 20~30 seconds. Compressor relay obviously works, but also switched with another to see if it was faulty, same cycling. Checked pressure of 134, steady around 45psi. I added more and got up to 65, but no difference in temp out of vents or compressor cycling. When I disconnect, then reconnect gage, pressure reads 45. Also bypassed high? or low? switch on dryer bottle, and with compressor running for a few minutes straight, no difference in vent temps.

I think I have a blockage in a line somewhere. If that is the case, how do you track it down? This van has just under 100k, and no accidents.

Is there anything else that can be checked? I have a pretty grumpy wife right now.

[Toolman5523]

The restrictions form the most where the passage is the smallest ...duh. That leads you to the line that houses the orifice tube. However if you have a restriction due to contamination, then your comp is coming apart. 45 psi is plenty high for low side, 60 is way too high for low. The way you want to look at what your pressures should be is low press. is equal to the temperature at the evap. While your high should be about 2.5 times ambient temp. up to 90 degrees. Bare in mind that humidity will play a significant role in temperature and pressure. One of the easiest ways to test for a restriction is the touch method. Run your hand along a line a feel for major temperature diff. If you find frost built up, or if it suddenly changes temp. you have probably found your problem.

['90 Escort Man]

A/C is now fixed, but here are the items that I learned that can benefit everyone:

1) Don't trust the 'free' gages that come with refrigerant recharge kits. 'Free' equates to horribly inaccurate. I checked my system with a higher quality gage, and refrigerant was low - no blockages!

2) When running max air, run max air - including rear air. I was not taxing the system fully and getting an accurate reading with just front air at max.

3) Read all problem responses contained within A/F forum for your particular model. Someone much smarter than I stated in a previous A/C problem response that a compressor that cycles quicker than normal means low refrigerant. That lead me to think that my 'free' gage was suspect.

Thanks to all who read, and particularly to Toolman5523 who offered advice.