injector/fuel pump

[mustangjoe02]

just wondering, if you have upgraded injectors, do you have to upgrade the fuel pump?

 

[wmburns]

How much HP are you making? How much HP do you plan to make?

The fuel pump should be sized to match. A needlessly large fuel pump can cause it's own set of problems. The symptom is different depending upon return or return-less fuel system.

Not a lot of information to go on. Not proud of your ride? Sure seems like it due to the lack of detail/effort in the thread.

 

[mustangjoe02]

im just wondering because im pretty sure i have 24# injectors (on the car when i bought it) but when i tune for them, its like its harder to start the car on a cold start. however runs fine after that.

 

[Maxpowers]

That's a bad tune. If the car runs fine and has power after it starts, then it obviously isn't the fuel pump.

 

[mustangjoe02]

arent light blue injectors usually 24#? ill know for sure when i change spark plugs next week and look at them closer

 

[trinity_gt]

An 02 GT pump is more than capable of working with 24# injectors.

How are you tuning for them? What tool are you using?

The plugs won't tell you much. They'll most likely be white-ish or tan because the PCM operates in closed loop most of the time. The amount of fuel delivered through the 24s during these conditions will be the same as that delivered through 19s. If you've got problems starting when cold it's likely the "tune" is still incorrect as Maxpowers suggests.

 

[mustangjoe02]

using my sf3 sct. but that helps alot. thanks guys

 

[wmburns]

im just wondering because im pretty sure i have 24# injectors (on the car when i bought it) but when i tune for them, its like its harder to start the car on a cold start. however runs fine after that.

Hard start could be fuel pressure leak down. Try cycling the key on/pause/off several times without cranking. Does this improve starting? If so, suspect fuel pressure is leaking down between starts.

 

[mustangjoe02]

how would you know for sure if thats what it was? how to fix also?

 

[wmburns]

So what are the results of the key cycling test?