What did i do wrong?

I have a 99 boxster. Last week driving home from church my lil b started idling all funny. idle would just fly up and down between 1400 and around 2000 rpm.
Reading up on forums i was pretty sure it was the maf as when i unplug car runs fine and dont miss a beat. Pluging it back it in it goes back to the same problem.
I replaced the maf sensor with one from buy-auto parts.com and when i plug it up same problem. Buy auto parts offers 1 year of warranty and is an authorized bosch seller.
What did i do wrong?
I do have techart intakes with k and n if that helps. As well as tpc supercharger kit with other bolt ons.



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This post was auto-generated based upon a question asked on our tech article page here:

[Nick at Pelican Parts]

Try disconnecting the battery to clear the ECU adaptations. Also check for a vacuum leak as this can also throw off the mixture.

- Nick