Thanks sixto and turbodiesel for your replies. I had a chance to do another test drive again this evening and, unfortunately, the rpm fluctuation is less (+/- 50 rpm) but still noticeable above 3k rpm in 2nd and 3rd gear. No surge was noticed in 1st and I'm too far away from the highway to check it out tonight in 4th . I guess it must have wishful been a combination of tiredness and wishful thinking, on my part, when I stated yesterday that the rpm fluctuation had gone away after plugging the ambient air intake.

Hearing what turbodiesel said about his SDL, I am not content long term to be mistaken for a "giggle head" as I roar by other drivers.

Is there anything I can do to test whether the alda is the problem with this car?

How about other possibilties? I noticed a little wetness at the base of the #2 injector. Could a an injector problem cause the rpm fluctuation?

I have not changed the main fuel filter since acquiring this car. The inline filter appears to be spotless. Could fuel starvation produce these symptoms?

Thanks again for any more ideas...