Found this on a fuel economy site. Wonder if it has has any merit???
Cover Oxygen Sensors with Aluminum Foil: Wrap your oxygen sensors in the exhaust pipe with 7 to 10 layers of shiny foil.
Advantage: The car computer system depends on the oxygen sensors to adjust the air-fuel mixture being fed to the engine. The cooler the exhaust gases, more fuel gets sent to the engine. The hotter the exhaust gases, less fuel will be sent to the engine.
Directions: To seal maximum warmth inside the exhaust pipe, insulation in the form of Reynolds Aluminum Foil is employed to insulate the oxygen sensor. Wrap five inches in front and five inches after the sensor to keep it much warmer. We double a one-foot section of foil and wrap that around the pipe and around the sensor itself. Do not remove the sensor. Then we repeat the process four more times. Finally we use .030" copper or aluminum wire to wind around the aluminum foil to keep it from blowing away and be sealed against water. The wire comes from any welding supply. The goal is to fool the car's computer into sensing too rich a mixture so it adjusts with a slightly leaner mixture and possibly a slight advance in timing. The end result is smoother engine operation and better MPG. This trick is especially important in severe winter climates.
I have tried this one and normal rules are if an oxygen sensor gets hotter it is lean and tells the computer to richen, but the oxygen sensor doesnt work unless temperatures are above 600deg in the exsaust which i found out on a site so the computer if it doesnt get a response from the oxygen sensor automaticly richens the mixture.
I found this hard to believe but have tried it and since the engine is 20% quiter and alittle bit more efficent.
When you do this just think what you can do to the intake air sensor. Me personally i would add hot air. I cant do this one cause i made a manual control to trick the computer : see below
Use Warm Air Intake:
Modify intake to draw warm air near radiator.
Advantage: Deliver warm and smooth air to the intake for best MPG.
Directions: Disconnect the cold air hose or housing from the fender well. Remove filter. Clean up the parts. Bore about 10 1-3/4 inch holes into plastic housing (if this applies) to draw air from the engine compartment directly to the air filter. Deburr the holes and clean the parts. Plug up the cold air inlet leading to the air collector box. Reinstall the air filter assembly. This will improve the engine Thermal Efficiency and mileage.
I am to try this one next week. Basicly i would just make a shroud to sux intake hot air from the radiater with out any extra cold air coming in.
George Wiseman from Eagle research has done simular to this but using heat off the exsaust manifold with good results.
Cover Oxygen Sensors with Aluminum Foil: Wrap your oxygen sensors in the exhaust pipe with 7 to 10 layers of shiny foil.
Advantage: The car computer system depends on the oxygen sensors to adjust the air-fuel mixture being fed to the engine. The cooler the exhaust gases, more fuel gets sent to the engine. The hotter the exhaust gases, less fuel will be sent to the engine.
Directions: To seal maximum warmth inside the exhaust pipe, insulation in the form of Reynolds Aluminum Foil is employed to insulate the oxygen sensor. Wrap five inches in front and five inches after the sensor to keep it much warmer. We double a one-foot section of foil and wrap that around the pipe and around the sensor itself. Do not remove the sensor. Then we repeat the process four more times. Finally we use .030" copper or aluminum wire to wind around the aluminum foil to keep it from blowing away and be sealed against water. The wire comes from any welding supply. The goal is to fool the car's computer into sensing too rich a mixture so it adjusts with a slightly leaner mixture and possibly a slight advance in timing. The end result is smoother engine operation and better MPG. This trick is especially important in severe winter climates.
I have tried this one and normal rules are if an oxygen sensor gets hotter it is lean and tells the computer to richen, but the oxygen sensor doesnt work unless temperatures are above 600deg in the exsaust which i found out on a site so the computer if it doesnt get a response from the oxygen sensor automaticly richens the mixture.
I found this hard to believe but have tried it and since the engine is 20% quiter and alittle bit more efficent.
When you do this just think what you can do to the intake air sensor. Me personally i would add hot air. I cant do this one cause i made a manual control to trick the computer : see below
Use Warm Air Intake:
Modify intake to draw warm air near radiator.
Advantage: Deliver warm and smooth air to the intake for best MPG.
Directions: Disconnect the cold air hose or housing from the fender well. Remove filter. Clean up the parts. Bore about 10 1-3/4 inch holes into plastic housing (if this applies) to draw air from the engine compartment directly to the air filter. Deburr the holes and clean the parts. Plug up the cold air inlet leading to the air collector box. Reinstall the air filter assembly. This will improve the engine Thermal Efficiency and mileage.
I am to try this one next week. Basicly i would just make a shroud to sux intake hot air from the radiater with out any extra cold air coming in.
George Wiseman from Eagle research has done simular to this but using heat off the exsaust manifold with good results.
