Originally posted by Tony2005:
Hmmm, it might be better to try removing a O2 sensor to see if it performs better if you are testing to see if the cat or precat is plugged.
True dat!
The MOST accurate way to tell is to put a low pressure guage on the upstream EGR pipe nipple for the DPFE. This will give you the actual exhaust pressure before both cats.
The pressure should be less than one PSI steady as the engine is revved (short spikes of up to 3 PSI are OK).
"Those who cannot remember the past are condemned to repeat it" -George Santayana
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