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Lean with High NOx and HC 900

Hi all,

Looking for some advice.

1993 non-EGR 945 turbo.

I recently installed a air/fuel meter. The meter shows lean at WOT. In addition, I have a recent emissions report that shows high HC and NOx.

From reading the FAQ it makes sense that I would see the combination of lean and high HC and NOx, my problem is I do not know how to find the problem.

First I will give you the numbers:

Measure Max Allowed Result
HC(PPM) 130 113
CO (%) 0.70 0.15
NOx (PPM) 1522 1513


Ther are no codes stored on the OBD.

I checked all air intake today to check for leaks and found none, although I doubt this would be a problem as I have a turbo and at WOT I figure I would be losing air instead of gaining.

The O2 sensor is only about a year old.
I changed the fuel filter about a year ago too.
The Cat is only about 6 months old.

That leaves fuel pressure?

One thing I can't find in the FAQ (except that it is difficult) is how to measure fuel pressure. Anybody got a walk-through? If it is fuel pressure, does that mean a bad fuel pump?

Any other ideas?

Thanks,
Ian






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New Lean with High NOx and HC [900]
posted by  ian f. subscriber  on Wed Jul 20 10:58 CST 2005 >


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