Fool the computer & change timing
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From: Spokane
Fool the computer & change timing
Years ago I did this and wanted to pass it on in case it helps someone.
On my 85 E-150 6 cylinder I put a variable resistor in line with the temp sender and remoted it into the cab. I found that the computer reads the temp sender and adjusts the timing depending on the engine temp. By adjusting the resistor I could fool the computer into thinking the engine was cold and it then removed some of the advance from the timing. I used this when pulling hills so I didn't get so much nocking from cheap gas. Goo luck.
On my 85 E-150 6 cylinder I put a variable resistor in line with the temp sender and remoted it into the cab. I found that the computer reads the temp sender and adjusts the timing depending on the engine temp. By adjusting the resistor I could fool the computer into thinking the engine was cold and it then removed some of the advance from the timing. I used this when pulling hills so I didn't get so much nocking from cheap gas. Goo luck.
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From: Destin/Ft. Walton Beach,
Hey, that's a great idea. That's even better then installing a cooler thermostat. They do the same thing, but your idea keeps the engine in the proper temp range. I'll remember that one. Where did you get the variable resistor. Is it like a rheostat?
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From: Spokane
In electronics circles it would be called a potentiometer(POT). Like the old radios. Old being 5 years ago. I panel mounted it and put a **** on it. Can't remember the resistance. 50k I think. I remember trying it in parallel and in series. I think I liked it best in series. It also changed the idle by a few hundred RPM when I turned the POT. Be careful, I also remember that when you change the resistance that the computer changes the fuel mixture. It might mess up your plugs.
Last edited by fordberg; Apr 17, 2004 at 09:30 PM.
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From: Destin/Ft. Walton Beach,
I believe that a POT wired as you described, functions as a rheostat. Potentiometers find their most sophisticated application as voltage dividers, where shaft position determines a specific voltage division ratio. However, there are applications where we don't necessarily need a variable voltage divider, but merely a variable resistor: a two-terminal device. Technically, a variable resistor is known as a rheostat, but potentiometers can be made to function as rheostats quite easily.
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From: Spokane
I usually reserve the word rheostat for a device that needs to handle a large load or lots of power. Like in the old trucks, they used rheostats to control the heater motors. On a three lead POT use one end and the wiper in the middle to get an adjustable resistor.
Last edited by fordberg; Apr 18, 2004 at 03:48 AM.
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