rlane5

I did a LQ4 swap in a 86 Vette. I have a sine-wave VSS and when car get to 76 MPH @ WOT the car will buck and jerk. when I back out of the throttle and move at 76 it runs fine. When the VSS is not connect the car will rev and move faster than 76 mph. My question is do the 12200411 PCM need a square-wave VSS, or a Sine-wave (AC) VSS
Randy

RonSSNova

iTrader: (3)

Sine wave. All the modern speed sensors are 2 wire Hall effect.

Is the speed reading correct?

rlane5

I have to check, to see how accurate the speedometer is, I know it's not that far off. I have a VSS off an early to mid 90s GM transmission.
Randy

RonSSNova

iTrader: (3)

Can you post your tune?
I'm wondering if maybe your speedo seems correct, but the program in the PCM thinks you are going way faster triggering a speed limiter in the PCM.

Do you know how many teeth are on the reluctor? Is this a TH400 perhaps?

Ron