I own a 93 Miata and as far as I know the wiring is stock on the vehicle. I have recently made a MS3X using the turbo kitty site. I think I have made it right but that may very well be my problem. When putting it in the car I did the jumper in the old MAF connector for the fuel pump and attached my IAT. I plumped my line for the MAP sensor and unplugged my stock TPS (I'm waiting on my vtps to come in). I also put the 1k resistor in the diagnostics box from IG- to B+. Also my wideband is wired in by using the power and ground from the buzzer under the dash. When plugging the ms3 in and turning the cars power on to load firm ware I cannot connect to it. Both of the fans come on and stay on but I cannot hear the fuel pump priming. I don't know what to check from here I would just like suggestions on what or how to trouble shoot the ms3.

 

Bump?

 

Did you install the proper drivers for your USB cable? That's usually a good place to start, I believe the cable from DIYautotune needs FTDI drivers. If you've already done that, check out the manual here http://www.msextra.com/doc/pdf/MS3XV30_Hardware-1.3.pdf at page 216 for testing instructions. You want to make sure the MS3 daughter card is getting proper power first.