i have a 98 mirage with a MAP sensor not MAF. now will a turbo trigger a CEL since the MAP sensor sees vacuum as a norm, and boost is not. also i know it is a good idea to get a AFR meter but is it really necessary?, besides being able to know if it is going too lean? thanks in advance.

 

getting an afr guage is the most useful when tuning a car. But i dont think that a turbo wil throw a CEL unless the car is running too lean. I would get the code and see what it throws.

 

No but you will hit fuel cut, your maf sensor is only ment to see soo much air, if it sees more then what its suppose to instead of adding fuel it will cut fuel to the motor and stall. To fix this you need to get a voltage clamp that blocks readings over your max allowed tolorence.

Yes a afr is nessicary, when you boost the car the stock fuel system wont be able to keep up with it you will just lean out and weld a piston into the block. You will not only need a afr for tuning but a wide band. The afr gauges autometer, and companys like, sell afr gauges that hook up to the stock o2 sensor which are narrow band o2 sensors. They specialize in reading stoitchomitry, part throttle or close loop, where a wide band o2 sensor reads the rich end of the scale, wot or open loop. The o2 though needs a special gauge to read its out put becuase a blinky led gauge isant percise enough. Aem's wide band kit is the most basic which offers a digital numeric read out along with a blinky led. Generally those run 300-350. Also you will need a new fuel pump, a fmu or even better a sfmu, a fuel pressure gauge, injectors, and depending on how the fuel system is set up some ss fuel hose.