yep, you got one. a MAP (manifold absolute pressure) sensor is just an air-pressure sensor that measures the vacuum/boost* of the intake air. that signal, combined with the IAT ( intake air temperature) sensor let's the computer figure out approximate air density and helps it adjust the fuel mixture. some cars like the 1G turbo engines have a MAF (mass air flow) sensor which does basically the same thing.
*our MAP sensors mostly read vacuum. they can read a little boost, but not too well since they weren't designed for it.
Oh humm...in regards to turbo charging our cars then...the STAR instructions says to install their modified MAP thingy for 1997+ cars. SO I was wondering why 1995 don't need that...?
well, i ain't wyatt, but i can still enlighten you. Our 95 cars don't need the check valves that come with the star kits. nor does it need a voltage clamp on the map sensor like the hahn kits come with or the VC1 that alot of star owners use. The 95 ECU is slighty different than the 96+ ECU's. It won't cut fuel if the ECU sees a value of over 4.7 volts being returned by the map sensor. So, if the map sensor sees boost, and the value goes over 4.7 (4.7 is the voltage that it returns when the pressure is at 0, or 1 bar of barometric pressure. No vacuum or boost) anyway, if the 95 sees boost, it won't freak the ECU out, if the 96+ sees boost( a value over 4.7) it will cut fuel and your car will buck)
I don't know why the star instructions say 97-99. I believe all of the 96 cars freak when they see boost. correct me if i am wrong. but it has alot to do with the switch to OBD2 that occured in 96.
anyway, be glad you got the easier fuel system to deal with when you bought your 95.
#941, "Jason got it All :)" In response to Reply # 3
Thas pretty mucch it. And, 4.7v happens at just over .5psi of boost (at least in my car) The hole MAP sensor stuff trips me out because there are a lot of people out there that don't even have a VC1 (Voltage clamp) and don't have any problems what-so-ever. Explain that one to me Wyatt Leras http://www.turbogs.dsmpower.com 98 Eclipse GS Star Stage 5,000 Turbo kit
#942, "RE: Jason got it All :)" In response to Reply # 4
I think that has to do with the fact that we are using a mechanical fmu to provide fuel when in boost. That is what is really providing fuel. The VC1/check valves/whatever is only smoothing out a flat spot that would occur when the ecu exceeds 4.7 and the car transitions into boost and to the rising rate fmu.
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