92 240sx Running problem at 2500 rpm

[92-240sx]

We resently put a COLD AIR INTAKE SYSTEM in my 1992 240sx and removed the air box and hooked everything up correctly after installing the intake we added a mod chip to the IAT sensor correctly hooked up and reset the computer with no engine lights on at all. It idles about 900 and when driving the car and getting to about 2500 rpms it starts to buck like jerking likes its not getting enough fuel or something the cars runs great but when it gets to 2500 it acks really bad what could be the problem.

Thanks,Jeff

[92-240sx]

The mod chip we used was the Diablo Performance Module. Also we un hooked the module and hooked the stock IAT back up and it runs like 500rpms and then it dies if your rev it up and also bucks at 2500 rpms.

Thanks,Jeff

[NISTECH]

check your connections on your afm be sure you got a good ground circuit.

[92-240sx]

Do you know what color wire is the ground on the AFM is it the white wire ? I have three wires going into the AFM white,black and black w/white stripes. I did a check on the black with white stripes and its the hot wire.

Thanks,Jeff

[92-240sx]

OK i have removed the mod chip and im not going to be using it at all. I hooked the wires back up to my afm and it doesnt do the jerk thing at 2500 but the car doesnt want to idle after a rev and it seems like its running to rich and not ackting the way it should be what should I do to correct this problem do you think I fried my afm module should I go and buy a new one. Any help would be great. The only thing I changed on my car was a cold intake.

[NISTECH]

comfirm its bad by checking all three wires.the white is the signal wire it will very by amount of air flow going through it. the gnd wire black one should read .02v or less at all times, the black should be supplied voltage at all times and the white one should read around 1.3 to 1.5 volts at idle. if the white wire is higher or lower then that it is likely damaged. should be a signifacant difference like .2 volts either way.