You have a bad vacuum reservoir or leaking vacuum line. Vacuum is usedd to control the air duct doors in your system and when you accelerate, the vacuum supply is greatly reduced...causing the duct doors to "default" to the defrost position.
Loose belt - will sound like a screeching noise.
only if it doesnt have fluid.
Brake Booster needs replaceing
On a 1991 Lincoln Continental : I'm not a mechanic / technician but I have never heard of aluminum heads for the 3.8 litre Ford V6 engine So , I would assume they are cast iron
Would have been built for R12, can be converted to R134a.
You might need freon
No, as being a master mechanic, it would have nothing to do with it.
A person walking in a straight line at a constant speed would not be accelerating. A person standing still in one spot would not be accelerating.
That would be found on the transmission where the linkage hooks up.
It isprobably not getting fuel or not getting spark.
Check that the wire on the rear defroster is connected to the defroster. If broken off repair it.
There is a problem with the SRS...have a dealer check it.
Lincoln Continental, although some people would call this a boat, not a car.
Check the air bag suspension. Also, the pump may be bad.
Cartalk.com--The Tappet Brothers know all.
I had the same issue with mine...it was the crank/fuel sensor...cost - 50.00 for part
Yes. You can travel in a circle at constant speed, but you would still be accelerating because your direction would be changing constantly.
autozone.com shows DOT 3 or 4 ( I would use 3 )
Check the fuel filter or the fuel pump.
Only when accelerating, I would suspect a broken motor mount or bad CV joint.
Mainly because you don't need a fogged up windshield if you are driving fast. Seriously, the defroster setting is where most autos go to if there is a problem with vacuum. If nothing worked in your dash controls, the one thing you would still need would be the defroster, so that is the default setting. Now, when you accelerate fast, the throttle is wide open, and there is no vacuum, or it is very low, so with low vacuum the control reverts back to defrost. It would be the same as if you un hooked a vacuum line and did not feed your dash controls, you would only have defrost.
the heater controls are run on engine vacuum. When a engine is accelerating it has a drop in vacuum. There is a one way check valve that keep vacuum in the heater circuit that has gone bad. You could have it fixed or you can deal with it, its not that big of a deal
On the '83 Conti, there should be a cigarette lighter at the bottom of the console . You'll have to buy an adapter for your computer to plug into it.
there is not a reset, also you have to do is get the seats where you would like to have them and then press the memory button again and it should set to the new position.