I didn’t suspect the car is California equipped until last week when I did the duty cycle test. I checked with the dealer and they confirmed the car is California equipped. The yellow sticker in the engine compartment also states that the car meets California emission requirements.
I did the test again today with multimeter +ve (red) lead in socket no. 2 and -ve (black) lead in socket 3 of X-11 connector. I realize this configuration will reverse the Mercedes spec readings but I did that to conform with the Landis numbers. Something strange happened which made me start the test over again.
Test 1
KOEO
Pushed connector X92 button once -- red LED flashed once.
Pushed button again -- red LED was on continuously
Duty Cycle (DC) reading = 70.1% steady
Deflected the air sensor -- DC reading = 10.1% steady
Air sensor plate back to original position -- DC reading = 70.1% steady
The 70% readings didn’t make sense so I turned the key off then on again
Test 2
KOEO
X92 Red light on continuously
DC reading = 85.1% steady
Deflect air sensor -- Duty Cycle reading = 85.1% steady - no change at all
Start engine
DC goes to 0.00% slowly (noticed X92 red light was off)
pushed X92 button twice again to get continuous red light on
DC reading bouncing around 80%
Engine revving at 2,500 RPM -- DC reading bouncing around 69%
Back to idle -- DC reading bouncing around 78%
KOEO -- DC reading = 85.1% steady
I don’t know what caused the 70.1% reading in Test 1 above. However, it seems that in the second test, DC reading at 2,500 RPM (69%) is within +/- 10% of DC reading at idle (78%) but just barely, hence my original questions: Are these readings normal and should I go through the trouble of breaking away the original aluminum idle adjustment tower to get a better DC reading?
Thank you