Hi all, I have been having some problems with my heat-A/C;first blower fan only works on 1-2-3, not 4, and when I first turn on A/C I have cold air for about 2min, after that its pretty much not cold. i have a case of 134a as well as the low pressure gage/filler hose. when i install the hose the needle in my gauge goes to red zone @ 100psi. and I'm quite sure I'm on the low pressure side, is this simply over filled? or is this something more ? I have owned the car about 4yrs and it has about 165,000 miles

 

sounds to me like your compressor is not kicking in, I would check that first. Do the ziptie trick, and go to the local junk yard and pull a resistor for the blower motor. That should fix the issue with not being able to get your speed to 4.

 

Check fuses as well - there's a separate fuse for the top blower speed. The AC does have both high pressure sensors (down by the evap) and a low pressure sensor (up by the firewall). Did you take your pressure sample with the engine on and when the compressor was engaged? If your system is cycling or not engaging due to low pressure you may need to jumper the low pressure sensor - I disconnected the LP sensor lead and used a paper clip to connect the two pins. The low pressure port for measurement is visible in Robert's vid - just trace the AC return line from the firewall, past the low pressure sensor down to the compressor.

 

First, I would like to thank you for responding, Ok, maybe I should clarify things a little. Per instructions when installing the freon/hose/gauge I have the car running, A/C on and look at the gauge, I am not seeing low pressure/freon I am seeing the needle in the red/high pressure zone, in this case it was at 100psi, when reading the instructions on the set up it says not to add freon and to take it to a shop as there is something else wrong where a professional would be required, I am asking if anyone has experienced this, or knows what it might be?

 

When your system is sitting (not running) both the high and low sides are equal. When you turn on the A/C the compressor will pull from the low side and raise the pressure on the high side. If you turn on your A/C and you see your compressor physically turning with the engine running then your system is not empty. Your year car only has a low side fitting (I think your aware of this). If the gauge never changes when you start the car and turn on the A/C with the compressor running then there is a fault in the compressor. I recently rebuilt a VW compressor doing exactly this. The part to fix it was inside the compressor and was allowing the compression to recycle internally causing the pressures to never change. A/C systems are designed to have a specific amount of freon in them. There is a yellow sticker on the passenger strut housing with the amount. When I work on A/C systems I dont even bother with 'topping off' since I have no idea how much has been lost. I pump down the system and refill with the recommended amount. That way you know you have it right.
Based on your gauge you have a problem with the compressor.

 

Walter, the "air conditioning only works for two minutes" problem is very very common on these cars. The clutches wear, and over time this creates a too-large gap. The clutch will pull in initially, but it gets warmed up, and eventually when it cycles it won't pull in again.

The gap should be adjusted. That has nothing to do with the blower problem, but I just wanted you to know that the problem with the compressor is not mysterious in any way.

 

Thanks for your reply, I will check this out when I have time. It does make sense though as in my commute I have shut it off when it's not cold air coming out, and after about five minuets of not running (the a/c, not the car) I can turn it back on and at times will blow cold air....sometimes it will continue blowing cold for the remainder of the commute....sometimes not. I think I was panicking because when I put the gauge (and canister) on with the car started and air on it had high pressure (in the red zone).

 

Your last post sounds similar to a problem I had with mine. I think the AC is tied to the electric cooling fan keeping the temp down. Mine would work fine as long as I was moving well, but it shut down and heated up when I got stuck in traffic. It turned out it was the electric fan not working and the AC is somehow tied into that or the temperature gauge. I fixed the fan - lose wire (and moved the clutch closer - pried with a screwdriver) and it works fine now.