hey guys, its been a while since i posted on here, i have a '90 RS with a 3.1 mpfi and i was recently adding a custom intake to the manifold but i dont know what to do with the ait sensor in the stock air filter canister, is there any way to bypass it? also where is a good spot to route an intake duct to the front grill from the intake manifold?

 

you can't bypass the sensor, but as long as it is reading a temperature close to the incoming air temperature you should be fine. personally, I would modify the intake to accept the sensor.

 

well here is my theory, if the sensor itself is just a variable resistor (varying on temperature) wouldn't it be posible to put an actual resistor in its place, i was reading my haynes manual which states that the sensor also delays EGR until the temperature reads 40 degrees f or higher, what does this mean and would it be a good thing to make it read something like 35 degrees that way the ex. gasses wouldn't be recerculated?

 

The computer uses the intake temperature in the calculations to determine how much fuel to inject. If you tell the computer the incoming air is colder then it is, the car will always run rich, and will have no power and get crappy gas mileage.
If you want to remove the EGR, do it the right way and get a chip with the egr disabled. There is practically no benefit to disabling the EGR. It will also hurt your highway gas mileage if you unplug the EGR because the computer will attempt to activate the egr. Usually, the recirculated gasses slow the combustion enough that the timing can be advanced for more efficiency. The computer will attempt to do that, but with the egr disconnected, it will start seeing knock counts and pull a ton of timing, ruining the efficiency.

 

either modify your custom setup or drill a hole in your plenum, somewhere behind the throddle body, maybe right at the back of the plenum, but if you put that sensor inside the plenum, youll lose power because your sensor is reading warmer air. if you put the sensor outside the plenum, like in you intake runner, it measures cold air and delivers more fuel for more power.

 

what about routing, what is the best way to run intake tubing to the front of the grill?

 

only because that is where it is designed to measure temperature. More fuel only equals more power up to a very fine line..