i have a 99 SI and i got a hold of two obdII -> obdI ecu jumpers. everytime i install the jumper and use an obdI ecu, the car bogs really bad, and when i rev up to 7k, the needle jumps right back down to 1k, and then back up. I've tried 2 different jumpers, and 3 different ecus, all from good running cars. Now, with the stock ecu in, it runs better, but i get a check engine light because i have a straight pipe on. i also have a jdm ctr ecu, but it doesnt run as well. any advice on where to start? thanks