The ford SVT people (the 1-800 number) will tell you that this is a "feature", put in place to satisfy EPA emission requirements, and they are not kidding here. However, I owned a 1996 SE (170HP Duratec), and never had the problem. I suspect the SVT engine has the problem because of its being in a higher state of tune (higher lift, longer duration cams, more agressive ECU software, higher compression pistons, etc.).
I have had this problem with my SVT since shortly after I purchased it in December, '99. I have tried the 7/32" plug in the air bypass tube and that does work for a little while. But then fuels apparently does puddle and the R's increase at Idle. Worse, because of the puddling, the engine will brake down under full throttle at higher RPM's because the sensors get conflicting readings.
This past week was especially bad. But yesterday, I think I may have solved my problem. It appears that a gas station I have been using may have had some contaminated tanks (water in particular). Yesterday, I purchased a bottle of water treatment and a bottle of fuel line cleaner (both STP), and the problem has disappeared!
I should note that if your engine not only hangs, but increases RPM's by several hundred or even 1000+, and stays in that range for 3-5+ seconds, you could have a bad throttle position sensor. Mine was replaced some time back and that particular piece of the puzzle was fixed.
Good Luck!
Paul V
2000 Black SVT
#379 out of 2150
Bone Stock
