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How to cheat high NOx? 700 88

Hi everybody,

Failed smog test on high NOx.(CO and HC are very good). I was told it's cat.converter - not cheap fix. I cleaned PCV, changed FI seals and checked for any vacuum leack.(but jiggle test some time good (on cold?) some time not quite (on hot?)).

How to test idle valve?

I'm off work now and trying to save money. I browsed FAQ and some archives - there are controversial suggestions.

1. a) Make engine really hot to pass NOx.

b) NOx caused by high burning temperature.

2. a) Setup ingnition advance to 0 to pass.

b) Returted ingition cause high temperature - high NOx.

3. How about methyl hydrate in the fuel? Does it affect NOx reading?

Who can shed a light regarding 1,2 and 3? What is correct "a" or "b"?

Thanks in advance,

Yuriy

PS: I did couple attempt:

1. Returted (almost 0?) ign.timing and low octane fuel - failed by 28%.

2. Normal timing (12) and good deal of methyl in tank - failed by 100%.






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New How to cheat high NOx? [700][88]
posted by  someone claiming to be Yuriy  on Wed Sep 26 11:47 CST 2001 >


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