Fix for low idle and/or stalling after ignition
 

I own a 2001 GT, 4.6L 8 cyl. About a month ago, idle was low and vehicle would stall frequently immediately after starting or when stopped. Ford dealership had no clue, replaced MAF (whatever that is), which was "out of range." That didn't do it, but cost me $500. Next, I was told fuel was contaminated, which I thought of. That wasn't it after all.

Auto Zone mentioned that problem may be caused by faulty by-pass valve (Part TV251). So I bought one for under $60 and installed it myself, since the replacement procedure looked to be ridiculously easy. The car works like a champ.

Anyway, a mechanic should at least identify this by-pass valve first before seeking a more expensive and least-likely cause for a low idle and/or stall.

I hope this helps folks...