I dont' know if anyone else has posted on this, but yesterday my friend showed me how to do an ECU self-diagnosis (on the hunch that I have a bad knock sensor). The ECU, a small metal box of sorts, is located behind teh center of the dash, and can be accessed by removing the small (I think always black) plastic panel along the inside of the center dash on the passenger side of the car. With the ignition switch on, you turn the screw on the side of the ECU, and wait for flashing light codes. 5 short pulses followed by 5 long pulses indicates normal operation. A bad knock sensor, according to the Haynes manual, is denoted by three short blinks and 4 long ones, which is the code I got. That code is for an 89-92 GXE with the VG motor, but I'm making an educated guess (based on the fact that I have all the knock sensor symptoms, and assuming that the ECUs between both motors are similar or the same) that the codes are the same for either. So, that confirmed my suspicions about my knock sensor - now to scratch up 350 bucks for a new one. I hope this helps anyone with a sluggish VE.

PS - My check engine light has never lit up for the knock sensor, don't rule sensors out just because you don't get a CEL. I'm guessing it has to be either disconnected, or physically destroyed, to trip the CEL. Also, I'm sure some bad knock sensors dont even throw the ECU self-diagnosis code. But hey, it's something to go on

 

PPS - When I took my car into the local nissan dealership to have it looked over for lack of power and bad fuel economy, they didn't test the knock sensor or take the codes from the ECU.

 

some errors stored in the ECU don't trigger the idiot dash lights. Not sure about the knock sensor since I don't have my FSM on hand.

Even though it says the knock sensor is bad, clear the codes, and then test again. It could just be something thats a reminent from a long time ago or a code that happened at random. I'd try that before spending a few $$ on a new sensor.