Unsolvable hesitation...

[ripped camel]

So this was happening before Jamie did the swap so it is absolutely unrelated to that.

From a dead stop when I hit the gas (3/4 throttle) the car starts choking like it's trying to stall and acts as though it has only 10% power. For whatever reason if I floor it when this happens it stops doing it and after that seems to run better. I have no clue what that is.

So far here is what's been changed (keep in mind this problem was there before any of the following were added, I'm just listing the things I've done so we know what it's not):

SVT 255lph Fuel Pump
98 trans swap
Mercon V full flush and fill
Mach 1 torque converter
New spark plugs
IMRC's cleaned (however I'm getting a Cel that they are stuck open)
Checked and replaced all coil boots
PCV
crankshaft position sensor changed

As usual search doesn't net any results and I've spent hours looking this up....

 

[slowmkviii]

A coil going bad?

 

[ripped camel]

A coil going bad?

Isn't the way to test that to run the car, and then pull one coil at a time? If you pull one, and there is no difference that is a bad coil?

 

[slowmkviii]

Normally but I had a miss only under load and I
got lucky I started replacing coils one at a time and it was
the first one I did #5 also check iac and look into the imrc code

 

[LaserSVT]

Tps

 

[ripped camel]

Okay so I'm on the right track then. They teach you in psychology never to tell people what your thoughts are in terms of a solution to a problem because then their feedback will be biased.

I was leaning towards it being a TPS or IAC problem. Switching individual coils I never thought off, but maybe I will buy one new coil and test out that theory as well. Thanks guys.....

 

[LaserSVT]

If you think about the problem its really only a couple different things it could be. Since it runs fine at 100% throttle but not 75% throttle then the places to check are the TPS (prolly has a dead spot) or the fuel pump driver having a failing FET.

 

[02LS8Lincoln]

my car was going the same thing then I changed out the plugs and new coils from ebay and all set...no more hesitation.....coils are the life of these engines.