I tested the theory, and I gained some good information.
I used a 50K potentiometer and plugged it into the coolant temp sensor.
The as the sensor's resistance climbs the OBD II shows the coolant temp dropping. If you unplug the sensor, the pcm reads -40 degrees.
If you have 0 resistance, the pcm shows over 300 degrees F.
It seems that 50,000 ohms will make the pcm see ~60 degrees F.
Anyway, to the results:
There are other factors such as intake air temperature, but the stuttering is greatly reduced for me when my temp is below 80 F.
When I dropped it to 60F and then accelerated in 2nd gear, the engine was fine with maybe one little hesistation or bump. When it hit about 3500 rpm, IMRC point it fell on its face because it was too rich.
So for me, the results tell me that I am way too lean below the IMRC point.
Bigger injectors don't help because the pcm scales everything based upon closed loop and part throttle readings. It just delivers the fuel that its fuel map tells it to based upon rpm, air and engine temp, and airflow. I guess this means I'm gonna need the SAFC or a custom chip.
I don't predict the new MAF I ordered to be able to compensate for this drastic difference in AF ratio above and below the IMRC point.
For those with the 2000 SVT's, check this out for verification. We may not have the same problem, but then we might.
warmonger
