Ok so i have a 93 civic with a B18c1 in it. I also have a Vafc in the car for tuning which i have not done because i need to get a wide band first so i just use it to change my vtec point atm. But anyway heres my problem/annoyance. when i turn my ignition switch on and let the vafc boot up the pressure shows -.5psi when the engine isnt even on. So I used the vafc to check the sensor voltage and it reads 2.810 on the map sensor. I know that it should be 3v and i was wondering if this is an acceptable voltage or if it could be causing a my engine to bog a little when I just tap the throttle under idle. also other things like if I try to rev it up real slow it seems to bounce and struggle to get up to where it should be RPM wise. I already posted this on honda-tech forums and they were no help so i came here to see if there are any actual intelligent civic owners. Also, just for fun, in case anyone might know why. My car (93 civic hatch) has a vin number that starts EH2 instead of the hatches EG. just wondering if anyone knew why. I tried to get pics of this but my POS camera put a glare over it every time and it was too dark to not use flash, i dont think it needs pics to explain anyway.