A/C Temp, Pressure, Cooling Fans, Overheating
07-28-2003, 08:37 AM
#1
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A/C Temp, Pressure, Cooling Fans, Overheating
About a month ago my car started blowing WARM air any place I stopped and idled. I thought it might need A/C charge so I checked the Low Pressure line and found the reading was over 100psi(too high or overcharged). There was COOL air when I was at speed but the compressor would not run long or when idling and the engine would begin to overheat. After getting the pressure down to 45psi my Compressor is now running at idle but the engine is overheating and there is NO cold air at all. I have no error codes and I don't know how to test a relay, so I was wondering if anyone had ideas? THe fuses were ok last time I checked.
07-28-2003, 11:32 AM
#2
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Re: A/C Temp, Pressure, Cooling Fans, Overheating
...maybe the most important part:
My Cooling fans are NOT running even with A/C on 4 and engine approaching hot (3/4+ temp gauge). This is obviously a problem and needs to be fixed (fuse, relay...???) but I wondered if this would affect the A/C as well (condensor would not be cooled?). Any ideas or suggestions are appreciated.
----
BTW, thanks already for the help with 0215 code. WD40 was much cheaper than a new EVAP canister and valve.
My Cooling fans are NOT running even with A/C on 4 and engine approaching hot (3/4+ temp gauge). This is obviously a problem and needs to be fixed (fuse, relay...???) but I wondered if this would affect the A/C as well (condensor would not be cooled?). Any ideas or suggestions are appreciated.
----
BTW, thanks already for the help with 0215 code. WD40 was much cheaper than a new EVAP canister and valve.
07-28-2003, 04:02 PM
#3
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The fans are a critical component of your AC. I had my passenger fan quit in my old '96 GXE, and my AC was non-existent while stopped. Replaced fan, AC went back to normal.
Both fans should be on whenever the AC is turned on (this goes for defrost, too). The driver's fan (primary) is supposed to turn on when the coolant temp exceeds a certain temp. It has two speeds to control the engine temp. The passenger side (secondary) will turn on when the primary goes on high, and whenever the AC is on.
On the advice of Nissan, when my secondary was out, they said I would have no problem with overheating without the secondary fan (and this was in Louisiana triple digits for a month while waiting for the part/money). The car ran fine, just no AC while stopped.
Because neither of your fans are working, I would not drive the car until fixed. That is because of the overheating (engine damage) issue. Since neither fan is working, I would suspect either a fuse, relay, sending unit, or wiring. But since there are 2 relays and 2 fuses under the hood, I doubt both would go out at once, but it is possible. I would suspect a sending unit (possibly engine coolant temp sending unit or whatever) is not sending the right signal to turn on the fans. Could also be wiring, or something as simple as something not plugged in. Check all of the above before you tear anything apart. If you have a Haynes manual or FSM, check them for troubleshooting. I can check mine later, so PM or email me if you need more info.
Dave
Both fans should be on whenever the AC is turned on (this goes for defrost, too). The driver's fan (primary) is supposed to turn on when the coolant temp exceeds a certain temp. It has two speeds to control the engine temp. The passenger side (secondary) will turn on when the primary goes on high, and whenever the AC is on.
On the advice of Nissan, when my secondary was out, they said I would have no problem with overheating without the secondary fan (and this was in Louisiana triple digits for a month while waiting for the part/money). The car ran fine, just no AC while stopped.
Because neither of your fans are working, I would not drive the car until fixed. That is because of the overheating (engine damage) issue. Since neither fan is working, I would suspect either a fuse, relay, sending unit, or wiring. But since there are 2 relays and 2 fuses under the hood, I doubt both would go out at once, but it is possible. I would suspect a sending unit (possibly engine coolant temp sending unit or whatever) is not sending the right signal to turn on the fans. Could also be wiring, or something as simple as something not plugged in. Check all of the above before you tear anything apart. If you have a Haynes manual or FSM, check them for troubleshooting. I can check mine later, so PM or email me if you need more info.
Dave
07-29-2003, 06:23 AM
#4
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The first problem is neither of the fan motors operate without shaking, beating, or rotating them. I took them out obviously and the little drain hole is dumping out lots of dirt. Maybe this will solve the A/C problem. Right now I am looking for the parts, debating on going to a junkyard since I haven't found just them motors and the whole assembly is nearly $200.
07-30-2003, 01:33 AM
#5
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If I remember right, I got my secondary motor from a local dealership for about $130. I do remember it did not come with the blades, just the motor. You may want to check Courtesy Nissan (www.courtesynissan.com). They seem to have cheaper prices than most. Also notice how one motor has 4 evenly spaced blades, and the other 5 or so unevenly spaced blades. A Nissan tech said they need to go back in the same way (both motors are identical, just not the blades).
You could possibly find good ones at a local junkyard for relatively cheap. Or, you could have your existing ones rebuilt (if it's possible) by a local starter/alternator shop or such.
I think your AC problem will be solved when you have working fans. When my one fan was out, the AC was very warm at stops, but worked fine at highway speeds.
To correct my above post, there are 3 fan relays under the hood by the battery. The FSM says one is for the primary fan low speed, one for its high speed, and the other for the secondary fan.
Hope you get this solved pretty quick with the least amount of financial pain.
Dave
You could possibly find good ones at a local junkyard for relatively cheap. Or, you could have your existing ones rebuilt (if it's possible) by a local starter/alternator shop or such.
I think your AC problem will be solved when you have working fans. When my one fan was out, the AC was very warm at stops, but worked fine at highway speeds.
To correct my above post, there are 3 fan relays under the hood by the battery. The FSM says one is for the primary fan low speed, one for its high speed, and the other for the secondary fan.
Hope you get this solved pretty quick with the least amount of financial pain.
Dave
08-01-2003, 11:41 AM
#6
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Join Date: Jul 2002
Posts: 36
Originally posted by Dave Holmes
If I remember right, I got my secondary motor from a local dealership for about $130. I do remember it did not come with the blades, just the motor. You may want to check Courtesy Nissan (www.courtesynissan.com). They seem to have cheaper prices than most. Also notice how one motor has 4 evenly spaced blades, and the other 5 or so unevenly spaced blades. A Nissan tech said they need to go back in the same way (both motors are identical, just not the blades).
You could possibly find good ones at a local junkyard for relatively cheap. Or, you could have your existing ones rebuilt (if it's possible) by a local starter/alternator shop or such.
I think your AC problem will be solved when you have working fans. When my one fan was out, the AC was very warm at stops, but worked fine at highway speeds.
To correct my above post, there are 3 fan relays under the hood by the battery. The FSM says one is for the primary fan low speed, one for its high speed, and the other for the secondary fan.
Hope you get this solved pretty quick with the least amount of financial pain.
Dave
If I remember right, I got my secondary motor from a local dealership for about $130. I do remember it did not come with the blades, just the motor. You may want to check Courtesy Nissan (www.courtesynissan.com). They seem to have cheaper prices than most. Also notice how one motor has 4 evenly spaced blades, and the other 5 or so unevenly spaced blades. A Nissan tech said they need to go back in the same way (both motors are identical, just not the blades).
You could possibly find good ones at a local junkyard for relatively cheap. Or, you could have your existing ones rebuilt (if it's possible) by a local starter/alternator shop or such.
I think your AC problem will be solved when you have working fans. When my one fan was out, the AC was very warm at stops, but worked fine at highway speeds.
To correct my above post, there are 3 fan relays under the hood by the battery. The FSM says one is for the primary fan low speed, one for its high speed, and the other for the secondary fan.
Hope you get this solved pretty quick with the least amount of financial pain.
Dave
On a cloudy day or at evenings/night, it gets cold as it can get, even when I stop.I checked the fans & both are working. As Dave has mentioned, the 2nd fan is for the A/C. However, it does not seem to have a low & high speed. It operates at only one speed. So, how do I know if it is running at it's full speed or not? Could the speed at which it runs be the cause for my poor A/C performance? I have checked other stuff like the low side pressure which is fine. I can hear a click when I switch the A/C on or off indicating that the compressor is working, etc,etc,
I just can't seem to figure out what's wrong with my A/C. The problem is those initial 15 min when I start driving after parking the car in the open on a hot sunny day. Any advices before I take it to a garage?
Thanks,
S
08-01-2003, 08:04 PM
#7
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Posts: 866
Try riding with the windows down, AC on when you first start driving to vent the insanely hot air out of the cabin. Mine takes a few minutes to get really cold (but not 10-15). Also, if you have the recirc button on, you'll be trying to cool insanely hot interior air instead of normal hot outside air. This may cause it to take longer (since your AC works fine when the interior isn't insanely hot like on cloudy days and evenings/nights). I only use my recirc button (if needed) after the interior has cooled a little. Most of the time, my recirc button never gets used, and I live in ridiculously hot/humid Louisiana. But then again, my AC comes out 39.4 degrees F cooler than the ambient air
Also, tint your windows if they already aren't. And those silver windshield shades drastically reduce interior heat, which is nice so you aren't holding on to that branding iron also known as a steering wheel (but remove shade before driving). AC works much quicker when a shade's been used.
Try these tips before you spend money at a shop. They may really help you out and save you money.
Dave
Also, tint your windows if they already aren't. And those silver windshield shades drastically reduce interior heat, which is nice so you aren't holding on to that branding iron also known as a steering wheel (but remove shade before driving). AC works much quicker when a shade's been used.
Try these tips before you spend money at a shop. They may really help you out and save you money.
Dave
08-06-2003, 07:24 AM
#8
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Join Date: Jul 2003
Posts: 104
OK, Here is the Fix, at least in my case.
First thing I did was find new cooling fans since this is an obvious problem for the engine in general. They can be bought for $170 a piece (dealer), $350 for the whole unit (dealer), OR $200 for the while unit at Autozone. It is the EXACT same unit. Ok, the stickers are different. That fixed the fan problem. Onto the A/C...
When I first checked the low side it was reading 120+ PSI (before I knew fans were out). This is WAY too much pressure. So, I pushed in the valve and got the pressure down to 20 or so. I put in a full can for a charge up to 40 PSI, which now gave me ZERO cooling and the engin was still getting hot. Then I got the cooling fans...
After putting in the fans, I rechecked the pressure on the low side, which was now 30-35 PSI. Ok, room for another charge... So I got it to 45-ish, ok a little higher and now I have cold air at the stops, driving, whenever.
So, it seems odd that these fans would die at only 5 yrs old?? But anyway, fans helped cool the air at stops, AND kept the engine from overheating. Only fans and a charge, $230. This would have been $350, plus coolant $40, plus labor... $100+. So, I figure I saved at least $250 or so.
Good luck to anyone with a similar prob. BTW, both fans should come on at high speed when you go to the highest A/C setting. That's a good way to check if you're not getting cool air at stops.
When I first checked the low side it was reading 120+ PSI (before I knew fans were out). This is WAY too much pressure. So, I pushed in the valve and got the pressure down to 20 or so. I put in a full can for a charge up to 40 PSI, which now gave me ZERO cooling and the engin was still getting hot. Then I got the cooling fans...
After putting in the fans, I rechecked the pressure on the low side, which was now 30-35 PSI. Ok, room for another charge... So I got it to 45-ish, ok a little higher and now I have cold air at the stops, driving, whenever.
So, it seems odd that these fans would die at only 5 yrs old?? But anyway, fans helped cool the air at stops, AND kept the engine from overheating. Only fans and a charge, $230. This would have been $350, plus coolant $40, plus labor... $100+. So, I figure I saved at least $250 or so.
Good luck to anyone with a similar prob. BTW, both fans should come on at high speed when you go to the highest A/C setting. That's a good way to check if you're not getting cool air at stops.
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