I have been experementing with this for about a year. There are several things that can be don't to increase gas mileage but the thing that works best is to replace the air intake temperature sensor with a fixed resistor.
I removed my air intake temperature sensor and it tests 50K at 60 degrees F with my ohm meter. If I breath on the temperature sensor and warm up to 98.6 deg F the resistance changes to 20K. This link shows the temperature range. https://www.aa1car.com/library/air_temp_sensors.htm
Warm air = thin air so the engine needs less fuel. I unplugged the wire from the temperature sensor then I inserted a 10K resistor into the end of the wire. My 99 Chevy Tahoe plug is perfect of pushing the resistor wires right in the spring clip holes. The engine starts and runs fine gas mileage is up a little because the 10K resistor makes the engine computer think it is sicking in 130 deg F air thats about = to driving across Death Valley on a hot day.
I experemented with lower and lower resistors. Now I am using a 1K resistor. The engine starts fine in the summer but it is hard to start in the winter. If the engine won't start on an extreme cold day I plug in a 10K resistor drive to work or to the store about 5 minutes into the drive I pull over and swap the 10K for 1K. Restart the engine and continue driving. The 1K resistor makes the computer think it is sucking in 250 deg F air.
I did a lot of tests with 10K resistor, 5K resistor, 2K resistor now the 1K resistor. I been checking the engine, checking the spark plugs, checking the oil, I don't want to damage the engine by making it run too lean. With the 1K resistor if I punch the gas pedal to the floor the engine sounds like it is starving for fuel and it will not pick up speed. But if I slowely push the gas pedal I can still pick up speed quick and pass cars on the highway. You have to learn to drive without a heavy foot.
My gas mileage is up from 12 mpg in town to 23 mpg in town.
Next I need to connect a 10K variable resistor in series with a 1K resistor and mount it on the car dash with 2 wires going under the hood to the temperature sensor plug. Turn the 10K resistor up to 10K including the 1K in series resistance will be 11K and start the engine. After the engine starts turn the 10k resistor down to where I want it for better gas mileage.
Once a year we all have to take our car to the emission testing place before we can buy new license plates. About a week before the test remove the fixed resistor and plug in the air temperature sensor. Disconnect the car battery cables over night for about 10 hours next morning reconnect the battery cables. This will clear the computer memory. Drive your car about 100 miles so the computer will store some memory then take it to be tested.
I was going to attach some photos but decided to wait and see if anyone actually needs photos.
I removed my air intake temperature sensor and it tests 50K at 60 degrees F with my ohm meter. If I breath on the temperature sensor and warm up to 98.6 deg F the resistance changes to 20K. This link shows the temperature range. https://www.aa1car.com/library/air_temp_sensors.htm
Warm air = thin air so the engine needs less fuel. I unplugged the wire from the temperature sensor then I inserted a 10K resistor into the end of the wire. My 99 Chevy Tahoe plug is perfect of pushing the resistor wires right in the spring clip holes. The engine starts and runs fine gas mileage is up a little because the 10K resistor makes the engine computer think it is sicking in 130 deg F air thats about = to driving across Death Valley on a hot day.
I experemented with lower and lower resistors. Now I am using a 1K resistor. The engine starts fine in the summer but it is hard to start in the winter. If the engine won't start on an extreme cold day I plug in a 10K resistor drive to work or to the store about 5 minutes into the drive I pull over and swap the 10K for 1K. Restart the engine and continue driving. The 1K resistor makes the computer think it is sucking in 250 deg F air.
I did a lot of tests with 10K resistor, 5K resistor, 2K resistor now the 1K resistor. I been checking the engine, checking the spark plugs, checking the oil, I don't want to damage the engine by making it run too lean. With the 1K resistor if I punch the gas pedal to the floor the engine sounds like it is starving for fuel and it will not pick up speed. But if I slowely push the gas pedal I can still pick up speed quick and pass cars on the highway. You have to learn to drive without a heavy foot.
My gas mileage is up from 12 mpg in town to 23 mpg in town.
Next I need to connect a 10K variable resistor in series with a 1K resistor and mount it on the car dash with 2 wires going under the hood to the temperature sensor plug. Turn the 10K resistor up to 10K including the 1K in series resistance will be 11K and start the engine. After the engine starts turn the 10k resistor down to where I want it for better gas mileage.
Once a year we all have to take our car to the emission testing place before we can buy new license plates. About a week before the test remove the fixed resistor and plug in the air temperature sensor. Disconnect the car battery cables over night for about 10 hours next morning reconnect the battery cables. This will clear the computer memory. Drive your car about 100 miles so the computer will store some memory then take it to be tested.
I was going to attach some photos but decided to wait and see if anyone actually needs photos.
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