Im hoping someone can help me.
My 2002 s40 wont start unless I put the foot on the gas.
I had a p0303 before and at 55mph, my car kind of hesitates or stumbles. the coil pack has a hair crack at the shft for both cyl 3 and cyl 4.
I think I have two problems:
(1) I think the IACV is bad.

Could some advise me? At this time, the car wont run unless I gas it. once I let go....gone. I could hear the fuel pump because it whines.

 

Fuel pressure regulator is bad. I made the same mistake and replaced the IAC for $200 only to have the problem continue. Then I read here about the FPR and that fixed it right up.

The crack in the coil pack could easily cause a misfire. Can you hear a 'pop, pop, pop' with the engine running from the spark jumping to the head?

 

It turn out to be the IACV. I cleaned it and didnt need to replace it. I thought it was fuel too but my fuel pump was running.
5 years ago I had the IACV replaced by the dealer. I looked at it and the part says
"FORD" I didnt know the dealer sells FORD parts.

 

I wrote bad fuel pump regulator, not the actual fuel pump. The regulator sets the fuel pressure across the injectors so everything works as designed.

I'm glad it was an easy fix though. I was not so lucky.

 

what is an IACV?
Idle control valve?

 

Exactly. Idle Air Control Valve.