Contour Enthusiasts Group Archives Forums Modifications General Mods Kill the A/C compressor...

Yup, that "low pressure" sensor seems to be the key to disabling the compressor. I'd be happy with rigging a "kill switch" for the compressor like that. Fool the computer into thinking there's no pressure in the system and the compressor won't go on.

jc-aimhigher: You're thinking like me, we should be able to make the a/c go on or off no matter the position of the HVAC controls. The problem with that is when you turn it on, it would stay on solid no matter what, just like in the "Max A/C" setting... You might find yourself turning the heat up to compensate cuz the car is going to frost inside! I rarely have it on the max setting...

If whoever finds the way would please share the info with us, it would be really appreciated!

Alright. My neighboe has been doing HVAC for the past 10 years and is one of the best at it - I've seen the results he gets. Turning off your compressor for defrost is stupid. First off, defrost will not work without the compressor, and in fact would most likely fog your windows. The reason for this is that when the compressor is on it dries the air (like any air conditioning system), makeing the air coming out of your vents more likely to absorb the moisture on the inside of the windshield.

In fact he told me a while back that the quickest way to heat your car on a cold day is to switch your HVAC to MAX A/C (max recirculates, where normal A/C brings it in form the outside) and turn the temperature to hottest. This works amazingly well! This will singe your hands on the steering wheel in no time. The options that make the A/C compressor go on are the two A/C settings and the two settings with defrost.

I still don't understand why the compressor bothers you, but then again I've lived with it my whole life since I grew up in Louisiana before I moved up here last year.

Seth, a couple things.

Many cars come without a/c or get old and don't work. The defrost still works in all but the hot and humid when trying to defog the windows.

The remote start on my wife's F-150 does not turn on the a/c compressor. So, when it's parked overnight in the winter and I leave the switch on defrost and fan on high, the windos still end up clear after 10-15 minutes. I learned that the compressor doesn't come on the first time I tried to use the remote start to cool it down in the summer. Still hot, sticky, sweaty seats after 10 minutes.

Most A/C systems work fine. However our Contiques use this amazingly inefficient compressor. Bonus is the non-linearity of the power it uses too. I noticed it the first time I drove the SVT. Never have I experienced such a change in engine behaviour.

A friend of mine used to have a 97 SE V6 5-speed. He sad it wasn't too noticable in that car and almost always has the A/C on. I labeled him an A/C freak as he does this in his home as well. Then he got a '00 SVT. He couldn't stand the A/C now. So, maybe it's more hit and miss with the power suck down. Feels like about 40Hp at times.

If your car doesn't do this, you can try mine at the next SVTOA meet and feel it.

Now, what you said for the most part is true. Running the compressor in defrost and other modes accelerates the task, but I'd rather wait an extra couple minutes at times than deal with the engine.

Aaron

Ditto here,

Of the six cars I've owned, my SVT is the first one that has a/c, and trust me, weather doesn't get much worse than Quebec in North America... Winters are cold and dry here, there's no humidity in the air that needs to be cleared for a defrost to work properly.

And on a hot day, that a/c does feel like somebody dropped a 4-banger in my car... I even got a comment from the g/f wondering why I kept going on/off throttle on the highway!! She couldn't believe it was the a/c dragging that much juice.

Oh, and trust me, when you start your car at 40 degrees below zero with 30mph wind, the poor engine will NOT run if the a/c is engaged... It's all weather dependant, but I can guarantee that up here, the fastest way to warm up your interior is NOT to have the a/c on... I need to turn it off because there's only .05% of my driving where I wish I had it...

I hate my a/c also. I just wish they would have offered to lighten my car and my bill with an a/c delete option.

Get over yourself! Did you ever stop to think that maybe someone doesn't want to be FORCED to run the A/C unit when they want to use the Bi-level setting (floor and windshield). Maybe we just want some fresh air flowing. Or heat to offset the sunroof open...
And guess what? There's still a seperate setting for "DEFROST" too.

Ford did this to save themselves some money. NOTHING to do with having to have the A/C unit running when blowing air on the front windshield. Hell. Even my wifes Cavalier LS has an on/off button for the A/C so you can run it (or not) on every setting.

Yes for the actual purpose of defrosting the windows (inital start up!) having dry air is ideal. Then "Poof" you turn the A/C unit off and keep the vent settings you like. Without the loss is gas mileage and performance we are stuck with stock.

I personally never use that setting for this exact reason. If every car up to this one that was the main setting I used.

Directly out of my manual for a 98.5 SE Sport
about using the FLR/DEF or the DEF mode...

"The A/C compressor (if equipped) will function to dehumidify the windows provided the outside temperature is above 10C (50F)."


It is made to work that way unless you modify it. I do not notice any pulsing of the engine at all when using the A/C. I also only notice a VERY minimal power loss with the A/C running. This is the only car I have had where I can say that about performance problems with the A/C on. It is a joy to drive in all weather!

About the option of A/C or not, our '93 Escort wagon has the A/C on or off option incorporated with the fan blower dial.

Keith W

I really do feel for you guys....i live in florida and about 98% of the time i never have to use the defrost settings and when i do the windows are clear with in about 30 seconds...
however living in florida i use my ac all the time and my air blows cold as hell(bad pun) if i leave it on i start to cold to drive. i can feel the difference w/ around town driving not real bad though and no where near as bad as you guys are saying (40hp....maybe 5-10 for me) all in all i love the way may hvac peforms

I ran my '98 Mystique all winter in Toronto. The temp shutoff works great until the engine compartment warms up, then the compressor cycles in and out. On the highway at good speeds it's a bit better, but in city traffic? You can feel the compressor rob you of hp every cycle.

All right, sorry to revive this old thread, but some of you sounded like you might have answers... Or maybe someone new??

Winter is full-on up here and this is back to bugging me to death. If I go fishing around the HVAC controls or the PCM, does anyone know if I have a chance of finding the wire that controls compressor turn-on to splice in a defeat switch??

Thanks in advance,