93 2.3 Ranger Only Starts With Gas Pedal Pressed To The Floor

[wbrockstar]

So a week ago I had turned the ignition switch on to manually push the truck forward so I could mow grass.Well yesterday,I hopped in the truck to start it and its dead.I had accidentally left the key in the run position a week ago and drained the battery.So I removed and recharged it overnight then reinstalled it this morning.I turned the key to start and it fired right up,but was running rough for about the first 20 seconds of run time then it cleared up & idled smoothly.After letting it idle for 10 minutes,I shut the engine off.I then attempted a restart and it just cranked over & over,but no start.I then floored the gas pedal while cranking and after a few seconds it started.As I began to give it throttle,it would stumble really badly for a few seconds then rev up like normal.Shut it off,waited a few seconds then started it again using the same method.I did notice everytime it started and moved from a stumbling idle to a normal idle,you would see some smoke passing by the passenger window from the excess fuel getting burned off.Is this more indicative of a defective fpr,ect sensor or leaking injector and are those 3 components the only possible causes for this issue?? I pulled the vacuum hose off the fpr and the regulator port wasnt leaking fuel.The hose didnt have wet fuel in it,but I didnt smell it for a fuel odor.
BTW- the no start unless pedal is floored condition just began today.
The truck is a backup vehicle so it doesnt get driven very often and has 200k+ miles on it.The ecm,fuel filter,timing belt,o2 sensor,evp sensor,evr solenoid and all ignition components have been replaced before,but the fuel pump,remaining sensors & 3 components listed above are the originals.They haven't been replaced.
It'll be tomorrow before I can work on the truck,but I appreciate any help/advice you guys can offer.Thanks for your time............ WBrock

 

[cbr600rx7]

Test your coolant temp sensor.

 

[tomw]

I'd check that pressure in the fuel rail is not leaking down instantly. If it is, I'd be checking that one of the injectors is not stuck open, or leaking. That would explain the excessive smoke seen on startup, and the need for WOT to get it running. Pool of fuel in the intake will make for very rich mix, poor starting, and once started, black cloud.
tom

 

[wbrockstar]

Test your coolant temp sensor.

If the ect sensor for the Ranger is listed as the same part number as my 91 5.0 Mustang,I can use the same volt/ohms specification chart as my Mustang to test the ect sensor in my Ranger,correct??

 

[wbrockstar]

I'd check that pressure in the fuel rail is not leaking down instantly. If it is, I'd be checking that one of the injectors is not stuck open, or leaking. That would explain the excessive smoke seen on startup, and the need for WOT to get it running. Pool of fuel in the intake will make for very rich mix, poor starting, and once started, black cloud.
tom

What would be the best time to check each injector for a leak?? Immediately after shutdown,during the no start condition,etc?? Would the following method work??
1) disconnect the inertia switch to disable the fuel pump then attempt a startup to clear out any residual fuel in the cylinders.
2) disconnect the harness from injector #1
3) reconnect the inertia switch
4) attempt a startup
If it starts normally without needing to floor the gas pedal,the #1 injector is leaking.
If you still have to floor the pedal for startup,the #1 injector isnt leaking so reconnect its harness and repeat steps 1-4 to injector #2.Finish the remaining injectors the same way.

So will this method work or is it gonna fail because the injector might still leak eventhough it was disconnected prior to the whole injector harness being energized??

If it wont work,whats the next easiest method to use??

 

[cbr600rx7]

I have no idea if you coolant temp sending unit is the same as a 5.0 or not but it should be located on the coolant hose running to your heater core. It's on the passenger side of your motor near the ignition coils. If it has failed it will tell the ECU that it's -40F. You should be able to test the resistance or the out put voltage but I don't have that info in front of me.

I would check your fuel pressure at the rail first. Start by turning the key on but with the engine off and fuel pressure should be at least 30 psi with 40 being perfect Start the engine and monitor fuel pressure it should stay above 30 psi. Unhook the vacuum plug on the fuel pressure regulator while the engine is running and pressure should increase by a few psi.

 

[wbrockstar]

I have no idea if you coolant temp sending unit is the same as a 5.0 or not but it should be located on the coolant hose running to your heater core. It's on the passenger side of your motor near the ignition coils. If it has failed it will tell the ECU that it's -40F. You should be able to test the resistance or the out put voltage but I don't have that info in front of me.

I would check your fuel pressure at the rail first. Start by turning the key on but with the engine off and fuel pressure should be at least 30 psi with 40 being perfect Start the engine and monitor fuel pressure it should stay above 30 psi. Unhook the vacuum plug on the fuel pressure regulator while the engine is running and pressure should increase by a few psi.

Yeah the same ect sensor fits the Mustang & Ranger.I was just making sure it gets tested the same way,as far as what its ohms value should be cold and hot.

I had a gauge mounted to it,but the feed tube broke off so I trashed it.I'll have to rent a fuel pressure test kit or buy a gauge before I'll have the chance to test pressure.Out of curiosity,do you know if the 93 2.3 model has two pumps or just one??

One high pressure pump in-tank

One low pressure pump in-tank (+)
One high pressure pump on frame

 

[RonD]

1993 Rangers just have the one fuel pump in the tank

All fuel injection computers have a Clear Flooded Engine routine, not a Ford thing
All fuel injection computers use a Throttle Position Sensor(TPS)

Clear Flooded Engine routine leaves spark on but turns off fuel injector pulses, so no fuel enters the intake/engine while cranking the engine over
Turn key on
Press gas pedal down to the floor and hold it down all the way
You are now in Clear Flooded Engine mode, its that simple
(I use Clear Flooded Engine routine every morning when starting my high mile 4.0l, I want oil to circulate before Cold Start, so engine cranks a bit before I let up on the gas pedal to get start up)

If you crank the engine and it fires or starts then you have gasoline leaking in
Clear Flooded Engine routine ends when engine RPMs get above 400 or you let up on gas pedal.

Clear Flooded Engine routine relies on TPS giving computer above 4.5volts at WOT(wide open throttle)
So if throttle cable is stretched then you won't get WOT and computer does not start Clear Flooded Engine routine

key off, put a stick against gas pedal and against the seat so pedal is pushed down to the floor
Open hood and see if you can open the throttle a little more, if so then.........
Google: Ranger throttle cable mod

Simple fix for stretched throttle cable

The Clear Flooded Engine routine can be used to find a leaking injector
Assuming TPS is working and Clear Flooded Engine routine is starting, disconnect Coil Pack wires, so no spark
On the 2.3l you only need to disconnect exhaust side coil pack, intake side doesn't spark until engine is above 400 RPMs, just FYI

With no spark put computer into Clear Flooded Engine routine and crank engine over a few times, now pull 1 spark plug from each cylinder, the WET one is the cylinder with the leaking injector


IAC Valve should open ALL THE WAY with Key on, this gives full air flow for starting engine, this is why fuel injected engines usually surge when started then drop to cold or warm idle level as computer closes IAC Valve to set that idle.
The fact you have to manually add more air, i.e. push on gas pedal, may mean IAC valve is not opening all the way

Remove the IAC Valve, plug in its two wires if you removed them
Turn on the key, IAC Valve should open all the way
Unplug the two wires and it should close
Plug wires back in and it should open again
Repeat as you see fit.

If IAC valve is not opening all the way then it may have been damaged by leaving the key on for that long, its the "brown out" voltage that effects most electric/electronic stuff, when voltage drops below 9volts as battery faded out to "dead"


"Gas pedal", we no longer have one, lol, it is now an "air pedal"
In the carb days when you pushed down on the "gas" pedal gas actually squirted out of carb into the intake/engine.
That no longer happens, pressing down on gas pedal lets in more air, and thats it, computer will respond by increasing fuel injector open time as RPMs increase.
So keep that in mind when diagnosing engine problems, i.e. "pumping the gas pedal" is just varying the air flow, not gasoline related.
Fuel injection is a better system, and has a different path for problem solving

 

[wbrockstar]

Thats some great trouble shooting steps Ron D.I'll get busy tomorrow with some of these things.I was hoping a 10 minute test & replacement of the ect sensor would solve the issue,but thats doubtful now.If I find one injector only leaking,would you recommend replacing it with a new/reman injector then pulling the other 3 and doing a thorough off the vehicle cleaning and oring/screen filter replacement on them or should I give in and buy a whole new set?? Do newer Rangers use the same injector/lbhr rating as my generation to where I could grab a low mileage set at Pull-A-Part or are the injectors totally different now??
Is it wise for me to just go ahead and replace the fpr with the one I had on my Mustang?? Its only got 4-5k miles on it.

The fact that the truck has been this dependable,for the amount of time Ive owned it plus the 300k miles its logged is unbelievable considering the very small number of parts Ive had to replace.Every single fuel component,except the filter,and most of the sensors are still the originals.That says alot about the quality of oem Ford parts.All ignition components,except the ignition switch, have been replaced though.Im not planning to sink a bunch of money into it,but it has to run well enough to be used for emergencies or a second vehicle.

I'll get to work tomorrow and try to update later on.Thanks for the help and guidance Ron D.
P.S. Ive read a bunch of threads you posted to and you definitely sound like you know the ins & outs of the Rangers,so your advice is very sound.

 

[cbr600rx7]

I would not replace the FPR unless it's bad. And it's very easy to test.

 

[RonD]

Thanks for the compliment

Pull-a-part fuel injectors can be OK but................gasoline turns into a sludgy varnish when exposed to air and time.
So they can be clogged up

Its not just the LBS rating but also the length and connector type when replacing injectors
1985 to 1997 2.3l injectors will work for your 1993
rebuilt set of 4 should run $60-$80
In 1998 Ford change to a higher fuel pressure so different injectors on the 4cyl

 

[wbrockstar]

I would not replace the FPR unless it's bad. And it's very easy to test.

I assume its not leaking since Ive already checked its port and the hose for fuel and its not stuck open because the truck wouldn't even start if that was the case.The only thing left that it could still do is stick closed.What symptoms occur when one sticks closed?? Will it not start because pressure is too high??

 

[wbrockstar]

Thanks for the compliment

Pull-a-part fuel injectors can be OK but................gasoline turns into a sludgy varnish when exposed to air and time.
So they can be clogged up

Its not just the LBS rating but also the length and connector type when replacing injectors
1985 to 1997 2.3l injectors will work for your 1993
rebuilt set of 4 should run $60-$80
In 1998 Ford change to a higher fuel pressure so different injectors on the 4cyl

Thats not bad at all.I thought they were gonna be $50-$60 each.Plus even if I found a 97 model Ranger,thats still a 20yr old truck,so its almost pointless to use something with that amount of age.Ok thanks for the info.

 

[tomw]

star: I assume its not leaking since Ive already checked its port and the hose for fuel and its not stuck open because the truck wouldn't even start if that was the case.

Not exactly. The 'return' EFI system adjusts the pressure by flowing fuel not needed back to the tank. It won't leak into the manifold as a leaky injector could. There are check valves built into the pump and regulator, which keep fuel in the fuel rail, ready for the injectors. If the check valve in the FPR leaks, it would allow pressure to drop, and the fuel would go back to the tank. The engine would start, though crank times might be increased before fuel is pressurized and available for the injectors to release.
If there's a leaky injector or check valve, it doesn't take a lot of fuel to lower the pressure to zero. For the most part, the expansion, ever so slight, of the fuel lines is the factor that determines how much fuel it will take to build pressure again. The filter, pump, fuel rail, and injectors are 'hard' and won't noticeably expand at normal pressure, while the fuel lines made of plastic will allow some expansion and volume increase under pressure. That is the 'volume' that will flow when pressure is relieved. The rest of the fuel should stay in the lines as it can only trickle out as air is allowed in to replace it. If there's no venting, the fuel will just sit, under no pressure.
tom

 

[wbrockstar]

star: I assume its not leaking since Ive already checked its port and the hose for fuel and its not stuck open because the truck wouldn't even start if that was the case.

Not exactly. The 'return' EFI system adjusts the pressure by flowing fuel not needed back to the tank. It won't leak into the manifold as a leaky injector could. There are check valves built into the pump and regulator, which keep fuel in the fuel rail, ready for the injectors. If the check valve in the FPR leaks, it would allow pressure to drop, and the fuel would go back to the tank. The engine would start, though crank times might be increased before fuel is pressurized and available for the injectors to release.
If there's a leaky injector or check valve, it doesn't take a lot of fuel to lower the pressure to zero. For the most part, the expansion, ever so slight, of the fuel lines is the factor that determines how much fuel it will take to build pressure again. The filter, pump, fuel rail, and injectors are 'hard' and won't noticeably expand at normal pressure, while the fuel lines made of plastic will allow some expansion and volume increase under pressure. That is the 'volume' that will flow when pressure is relieved. The rest of the fuel should stay in the lines as it can only trickle out as air is allowed in to replace it. If there's no venting, the fuel will just sit, under no pressure.
tom

If the diaphragm was leaking,fuel would get into the manifold,but it would get there due to vacuum drawing it in through the regulator vacuum hose instead of leaking into the intake like an injector.
I was thinking,since the regulator is at the end of the fuel rail to maintain a specific psi # to the injectors (which means its keeping the fuel rail pressurized to at least 40-45psi) if it were to stick open,wouldn't that prevent the injectors from getting the correct amount of fuel because the regulator isnt holding the pressure back at the far end of the rail,to maintain that constant pressure??
It actually seems like the fuel pump would continue running when you turn the key on,instead of doing its 2 second prime period and shutting off,if the regulator was indeed stuck open because you'd think the rail would never get fully pressurized since the regulator isnt stopping the flow of fuel?? Can you clear my thinking on this and can I assume
by your post that my fpr could still be bad eventhough fuel isnt leaking out of the diaphragm??
Thanks WBRock