car missing, need help!!!

[Uncle T]

I bought an 89 240sx with automatic transmission for my girlfriend, immediately replaced entire exhaust (oem not performance), injectors (one was leaking pretty bad) fuel filter, plugs, plug wires, rotor, rotor cap, air filter. Car ran great now under any once in drive the car acts like it's running on 3 cylinders. It does not do it under heavy acceleration but it does do it at any speed under light acceleration, but not until you put it into drive.

I'm thinking there may be a problem with the EGR valve giving the computer bad info but I was wondering if anyone had any other ideas before I go replacing unnecassary parts.

thanks for the help

T

[NISTECH]

check your EGR operation see if it is flowing by lifting up on the diaphram from under neath. If the engine stumbles your egr is flowing. then check for vaccum to the BPT see if it has at least 5in of vaccum off idle that means the vaccum is available to the egr. the next test would require you to hook up a gauge you can see while driving when you are accelerating not to hard light accel the vaccum should be available on the other side of the bpt(the vaccum hose that goes to the egr) if those three tests come out ok I dont think its your egr. If any of them fail tell me which one and I will tell you what you need to do next.