[mwebb]

VOLUMETRIC EFFICIENCY is what suffers at part throttle , compression is not changed , there is insufficient air fuel mixture to compress as
VOLUMETRIC EFFICIENCY has been reduced
increasing flow of
EGR improves VOLUMETRIC EFFICIENCY ,until it does'nt there is a limit

there is a closed throttle switch on that system and
there is a WOT switch
you can use inputs from those switches isolated with diodes to your controller to use an actuator to close off EGR flow at idle and WOT
to begin

the DPR controls lambda by changing / regulating upper and lower chamber pressure in the fuel distributor , you can adjust DPR slightly but you should not adjust it without a scope on the 02 / lambda sensor

you can measure DPR current by adding 1 ohm resistor in series to DPR
current should be about 0 to 10 ma engine running hot
voltage will equal current as E=IR voltage equals current times resistance but when resistance equals 1
current equals voltage , measure voltage across the resistor
set co to the middle of the bounce , about 5ma at idle , current will be changing always with 02 sensor input
center the bounce in the middle of the range 0 to 10ma

if current is negative you are in DFCO
current will go high on cold start , shows enrichment open loop
current will go high at WOT , shows enrichment open loop
never frack with CO adjustment without scope on 02 and current measring setup on DPR

installing an upgraded 02 sensor with a heater will improve everything
power up the heater with a relay switched on by ignition

the lambda sensor MUST be switching at cruise for the system to be in fuel control while EGR is functioning , lambda should not change by the addition of post cat inert exhaust as the cat will have used up all remaining 02 in the exhuast stream , in a perfect world , but in reality
you may need to change the CO adjustment slightly

you need a scope to do that
you can increase EGR flow until the 02 sensor starts to show misfire then back off a wee bit
02 sensor waveform at cruise on your car will look like this just as misfire begins 02 sensor is black trace
the 02 sensor waveform with no misfire will appear as a sine wave switching from 150mv to 850mv and back in 100ms or less at 45mph in gear at operating temp

02 sensor in black trace , pressure differential sensor in exhaust shows misfire , blue trace - secondary spark spark wave form in red trace


setup
laptop on front seat


on your system
02 sensor will show misfire before you can feel it , add EGR until 02 sensor shows misfire OR stops switching