Ok I just installed my VAFC in my 90 HB Si Using Apex-i H1-a wiring diagram and had some concerns, the first one was that after I set the vafc, I started the car and let it idal and noticed that the needle on my tach would be just under 1000 rpm's and on my VAFC it says it is Idaling at around 500 or so rpm's and when I rev the car and hold it I noticed that there was about a 500-700 difference in read outs from the vafc and the tach on my car, could it be that the needle on the car isnt that acurate?? Part 2 was the preassure signal says it at -600 or so Im not to sure about that but oh well, I checked throught the screen and the throttle position seem to be some what ok. This install was just a test to see if I have all the wires it the correct place so they are twisted and wirenutted on, (but plan on soldering it when 100% sure on all the connections) the car was on and runnig for a good 15 minutes reving the engine and idaling, and there was no smoke comming from the VAFC or the wiring harness, so I guess all is hooked up correctly but please let me know if Im wrong.
Any help is appreciated
Thanx

 

where did u crimp the wires to
the ecu plugs as the diagram shows

or where???

sounds funny as I did it myself and no problems expect it wasn't tuned
but that is normal until u get to the dyno or u try todo it urself
good luck there

 

ok I tapped into the wiring harness, I tinkered with it this mornig and I think i got I reset everything as the manual says todo, the only thing off is the voltage read out. It differs from the manual, but Im not sure if voltage read out is going to be the say, but rpm's are some what stable at idal the needle reads at just under 1000 rpm's and VAFC reads out 780-955, but noticed when reved to 3000rpm vafc reads 3044rpm's so I guess its fine just that the needle is a tad bit off. But if anyone know's if my voltage reading is supposed to be exact as in the manual or does it differ from car to car??? thanx, Oh yeah theres gotta be tons of people with the answer to this but no replies humm oh well but any help is appreciated

 

thats how i feel about everything i post, but you got everything right, i know the diagram your talking about. also factory tachs are alway like 200-750rpms off and not very accurate.
-joe

 

I agree that the factory Tach is off... The higher you go, the further out it is. I hit fule cut at an indicated 8000 RPMs until I borrowed a friend's tach.. Man was that off. :0

 

thanx everyone, humm i guess i shouldnt worry to much about the voltage read outs then.
Thanx