Power loss

[Jay B.]

I took my 2000 S in the other day to well know Porsche mechanic in my area because my spark plug tubes were seeping so he said lets change out the spark plugs as well since they looked aged and oily so I said do it so when I got the car back I noticed some power loss especially on the top end.
When I took the car in before the work the car ran great with lots of power so now it has lost that burst of power it use to have. I questioned the spark plugs he put in there and he said he replaced my 2 prong NGK's with some 4 prone Bosch spark plugs and he said that the spark plugs he put in there would have nothing to do with the power loss so he ran all kinds of tests and the MAF was fine and nothing was found of any vacuum leaks so then he tells me the computer in the car needs to basically reset itself to run right again. Is this BS or is this true?