My 1994 FZJ80 failed CO emissions test on High NOx. My question: What is is the best timing setting for reduced NOx? If retarded - how much? I reset it to 3 degrees BTD center according to the manual and the NOx level increased a bit on my second test.
Part two of my question: My rig has no heat shields on the cat's could this result in lower cat temperatures causing higher NOx levels?
Part three of my question: What is the optimal ambient (outdoor) temperature for the Emissions test?
Any and all help would be appreciated as I am far from being an expert.
Part two of my question: My rig has no heat shields on the cat's could this result in lower cat temperatures causing higher NOx levels?
Part three of my question: What is the optimal ambient (outdoor) temperature for the Emissions test?
Any and all help would be appreciated as I am far from being an expert.
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