Hesitation on steady throttle.

[SocalianSD]

My car has always had a slight hesitation on steady throttle when my car is warming up, never really bugged me. I just installed mustang 19lb injectors, miller maf, chip and ka motors intake and it has made the hesitation worse! What do you guys think it might be?

EDIT!
Did a search and found this thread, but my car isnt an eta so it couldn't be what his issue was. I'm thinking i should replace my o2 sensor.

http://www.r3vlimited.com/board/showthread.php?t=199232&highlight=throttle+hesitation

[dnguyen1963]

19 lb injectors...hesitation...there are so many threads on this topic already! Do yourself a favor and perform a smoke test.

[BMW_325i]

Are your injectors flowing 17 to 19lb at 3BAR (stock fuel pressure for B25) or something else eg M50, which are ~18 at 3.5BAR?

In the transition from cold start to fully warm the AFR's run a little lean, and is made worse by larger injectors that arent flowing enough, especially at lower revs.

I know this because i had exactly the same setup, but with a wideband o2 sensor telling me as much. The 'fix' was an adjustable fuel pressure regulator and pressure at about 3.9BAR (on m50 injectors).

I wasnt happy about that in the long term for the fuel pump so switched to V8 injectors with fuel pressure now at about 2.8BAR.

[Bmr]

My car has always had a slight hesitation on steady throttle when my car is warming up, never really bugged me. I just installed mustang 19lb injectors, miller maf, chip and ka motors intake and it has made the hesitation worse! What do you guys think it might be?

EDIT!
Did a search and found this thread, but my car isnt an eta so it couldn't be what his issue was. I'm thinking i should replace my o2 sensor.
http://www.r3vlimited.com/board/show...tle+hesitation

19 lb injectors...hesitation...there are so many threads on this topic already! Do yourself a favor and perform a smoke test.

Did you make sure to swap to 12v on your DME? If not the MAF wont read right. Also is the MAF on the right way. I've heard of people putting it on backwards. After resetting the DME I let my car sit for 5 mins then drove it out onto the road WOT like a redheaded stepchild.

[SocalianSD]

Did you make sure to swap to 12v on your DME? If not the MAF wont read right. Also is the MAF on the right way. I've heard of people putting it on backwards. After resetting the DME I let my car sit for 5 mins then drove it out onto the road WOT like a redheaded stepchild.

Yep i "T"ed the two wires that miller tells you to. also the maf is going in the right direction.