Hard start

[steveoelo]

I'm at a loss... Replaced fuel pump, filter, pressure regulator, distributor with about 60000miles (good tfi), plugs and wires. Truck takes forever to start when it sits for a bit after driving it. Did a pressure test and when running it was between 30-35psi. After sitting about an hour it dropped to like 20-25 so I figured pressure regulator. Does this sound like a fuel injector problem and if so how do I test for it? Truck runs good so assuming spark is not the problem

 

[RonD]

Do 50/50 test next time there is a No Start
Pull off air tube from intake
Open throttle and spray gasoline or Quick Start into the intake
Try to start

If if starts then fuel delivery was the problem
If it still doesn't start then Spark is the problem
50/50

Better than trying to guess

If you cycle the key ON and OFF 3 times that will cause fuel pump to run 6 seconds, 2 seconds at each key ON, 6 seconds = about 30psi
Then try to start
Key OFF Fuel pressure is held by the Check Valve in Fuel pump, and Fuel Pressure regulator(FPR)
Take the Return fuel line off the Fuel Pressure regulator, put a towel down under that port
Cycle key ON and OFF check if fuel is leaking out
FPR is set for about 42psi, so without engine vacuum, it should hold pressure just above 40psi so no fuel should leak out until above that.

 

[steveoelo]

I'm thinking the engine is flooding itself because if I rapidly tap the gas pedal it "seems" to start easier

 

[RonD]

If engine is OFF and key is on......
If you push gas pedal down to the floor and hold it down, computer will turn OFF the fuel injectors.
All fuel injection computers have this software, not a "Ford thing", often called "Clear Flooded Engine Routine"

So turn on the key
Press gas pedal down to the floor and HOLD IT DOWN
Now try to start engine
It should NOT start, just crank
(I do this every morning on my high mile 4.0l, to get oil pumped thru the engine BEFORE I start it)

If it does fire or start then you could have a leaky injector, but could also have a stretch throttle cable.
Key off, Press gas pedal down to the floor and hold it down with stick against the seat
Open hood and see if you can manually open throttle plate even more, if so.....
Google: Ranger throttle cable mod

Computer will restart fuel injectors if RPMs get above 400, i.e. engine fires a few times, or if you release gas pedal

You can use "Clear Flooded Engine" to find the leaky injector(s)
Assuming you checked throttle cable, so are getting FULL throttle with gas pedal, and injectors are being shut off

Cold engine
Disable spark, pull coil wire off distributor
Turn key on and off 3 times then leave it on, building up fuel pressure
Press gas pedal to the floor and hold it down, turn OFF injectors
Crank engine a few times
Pull out all the spark plugs
See which one(s) is WET with fuel, it has the leaky injector

 

[steveoelo]

It seems if I hold the pedal down it helps. The truck seems to surge at idle if you rev it up and the injectors tick bad (bad enough I thought I had the 2.9 lifter tick). If I run fuel injector cleaner through the truck would that make my problem better or worse? I have another set of injectors out of another truck that I could also rebuild but how would I test for leaky injectors before I rebuild them, or does it matter?