fritz:
CGX car nut:
fritz:

So that's  700l b of equipment in addition to the driver, and probably a passenger to monitor that equipment, right?  Smiley

Is there a mention of the corresponding total payload as stipulated in the specs for the EPA test cycle as a comparison value?   Smiley

The EPA probably has specifications on loads of the EPA test cycle; however, do realize that the evidence is very convincing that there is an on-off device related to the emission control system.  The cars operate well within the EPA  Tier2 bin 5 specifications when on the testbed but deviate substantially when on the road; however, only the NOx emissions are out-of-specification.  Emissions related to CO, CO2 and HC/THC are well within the limits.  

A review of the test results show evidence of a major engineering trade-off.  Either the NOx emission system does not meet the required reliability cycle or the performance falls off dramatically that the car is virtually "undriveable."

Don't get me wrong, I don't doubt in the least that someone consciously tried to cheat the system here, nor would I condone or defend it. There was obviously, in layman's terms, an IF ..... THEN .......  gate built into the engine control software diverting to the EPA compliant data map set IF the giveaway driving conditions for an EPA lab test were detected by the car's various relevant sensors.
In the absence of detailed knowledge of diesel emissions requirements and procedures on my part, I was trying to understand for my own curiosity:
(a) why the data mapping for optimised driveability could result in NOx emissions levels a factor of over 30 times greater than the EPA allows
(b) how the perpetrators could have dreamt that this could go undetected over time
(c) how the hell it did go undetected for so long.  

 

a) Can you elaborate on your question?  Basically, emissions controls were turned off, correct?


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2005 997S Blk/Blk