2.9L fuel pump/motor problems

[88liftedstx]

Hey guys im new to this website my older brother used to use it all the time when he was building his rangers so im kinda familiar with it but not so much anyway about 2 months ago i traded my car for a 1988 ford ranger stx 5speed it has a 6inch skyjacker lift with 33x12.50r15 pro comp mudd terrians so when i got the truck i noticed it was not a powerhouse because it had a 2.9 and 33s so i didn't think anything of it until one day i got in it and i went to pull out and it just died so i figured ahh i just stalled it so started it back up and i had to ride the clutch alittle bit just for it to pull out now when it started acting up a lot it cuts out going up hills in 3rd gear almost like it shuts off completely and comes right back on so i called up my brother an told him the whole story hes like it could be a weak fuel pump so i popped the hood and pushed down on the valve stem looking thing on the driver side of the motor and gas is just like flowing out like it has low fuel pressure now i wanted to get someones advice before i go out and replace both fuel pumps because my luck it will be a cheap fix but if any of you guys have any thoughts on what may be wrong i would greatly appreciate the help! thanks,justin

 

[adsm08]

Certainly does sound like low fuel pressure. I would put a mechanical gauge on it and see what kind of pressure the system can make before replacing anything. If you get low pressure get a fuel filter and put it in, see if things improve.

If you figure out it is a pump issue I would only do the high-pressure pump at this point, not the in-tank pump.

 

[RonD]

An '88 should have 2 fuel pumps, the low pressure pump(used for earlier carbed engines) and an added high pressure pump in the frame rail approx. under the drivers seat.
Between the high pressure pump and the engine will be the in line fuel filter.

On Fuel injected engines the fuel pump(s) doesn't run all the time, the computer turns pump on and off based on RPM and speed/load.
When key is first turned on you should hear both fuel pumps come on for 2 seconds then go off, this is the computer priming the fuel pressure.
You can turn key on then off a few times to test this and build up pressure in case system is leaking.
Test fuel pressure at the schrader valve("valve stem looking thing") after doing the key on/off a few times
The high pressure pump was added to the system when EFI was, so there is a factory splice near the high pressure pump that can corrode so high pressure pump doesn't come on(courtesy adsm08)
So have some one turn on the key while you check to make sure high pressure pump is coming on for those 2 seconds, if it doesn't come on but the in tank pump does then check that splice, and the ground for that pump.

The fuel pump Relay is what the computer uses to turn on and off the pumps, it should be located on the passenger side inner fender, there will be 3 relays in a row there, usually the fuel pump relay fails outright, but it can become intermittent just before it fails. If I remember correctly fuel pump relay has a Green base.

Yes, if fuel filter has not been changed and looks old change it, they are not expensive.

On the fuel rail there is a fuel pressure regulator(FPR), it has a vacuum line connected to it, remove this vacuum line and smell it for fuel.
If the FPR diaphragm leaks fuel is sucked into the intake flooding the engine.

 

[88liftedstx]

I replaced the relays I hear the pumps when I turn the key and also the truck wont start unless I pump or hold the gas pedal to the floor if I try to start it without pumping or holding it to the floor it will not start just keep cranking and if it does start it spits and sputters for a few seconds then will go to normal idle

 

[RonD]

Fuel injected engines have no "jets" like a carb did, so putting your gas pedal to the floor shouldn't effect anything, or pumping the pedal, on startup.

The throttle plate does have a position sensor, but the computer ignores it until RPMs are above a certain point, usually 500rpm, so engine has started.

When starting an EFI engine the computer will detect crankshaft turning via the CKP(crank position) sensor, the computer will then start the spark and fuel injectors, and open the IAC(idle air control) valve all the way, when engine "catches" idle should go up to 1,500+ rpms, and then drop as computer closes IAC valve to set cold idle, 1,000rpm, or warm idle, 750rpm.
So you should never have to touch the gas pedal when starting.

What could be happening is that there is too much fuel coming into the intake, opening the throttle(foot on the gas pedal) would add more air to the over rich intake.

I would crank engine over a few times then pull off the air plenum from the intake and smell for fuel, see if it is getting flooded.

If not spray some starting fluid or gas into the intake, replace plenum and try to start.

 

[adsm08]

Does this thing run well enough to make it a few miles down 11? Bloom is barely 20 miles from me. It will probably be less of a headache to look at this thing myself than ask question after question over the forum.

 

[88liftedstx]

ya it will make it if I baby it

 

[adsm08]

Well lets figure a time to get together and look at this thing. I am busy this weekend in the mornings. I don't know about Saturday afternoon yet.

Don't try driving it down here if it's not safe though. If it isn't safe to have on the roads I will load up some stuff and come out there to help you.

 

[88liftedstx]

its safe to drive on the roads I been the tie rod ends are getting bad the inspection is out I mean I drive it when it wants to run right but the little town im in no one really bothers like police and shit don't patrol through here so im not worried about inspection I don't really take it far because I don't know when it will cut out and stall out on me so im nervous about taking it far places hahah but when I used to drive to mount carmel and back it wouldn't have any problems besides when I took hills when it was cold it would cut out so before I do go anywhere decently far I usually let it warm up but when I pull out usually ill have to keep revving it up to keep the motor runnin after I rev it about 4 or 5 times that's when it runs right it can run extremely good one day like no problems what so ever but some days its like no your not going anywhere

 

[fightin irish]

2.9 starting problems

I too have a problem with my 2.9 when starting spins over about 6 times
nothing second 6 times starts but sputters then runs fine any suggestions? or same as above? crank sensor?, fuel filter? thanks for the help>

 

[JavaG66]

I'm having a similar problem here, so I thought I had found my answer right off the bat in these series of posts. Truck cranks up fine when cool, so I'm thinking flakey electronics. Replaced TFI, no change; truck still dies after about 10 minutes. I can hear fuel pump on the rail do its thing for a couple of seconds even when the truck is warm. No visual evidence of gas in the fuel pressure regulator vacuum tube; very, very slight smell of gas in the tube- I could be confusing the rubber boot smell. Installed a gauge to the schrader, 32 psi at idle. As the truck is about to shut down, pressure falls to 10 psi as it is stalling. The pressure starts falling right before you start to notice a drop in engine rpm. I can still hear HP pump running for 2 seconds after engine dies. Exhaust smells rich like engine was flooded. Depending on how hot the engine is, it may crank back up immediately, or I may have to wait a couple of hours before it starts again. Does this still sound like a fuel pump? Which one?
Thanks!!

 

[Zmiller0218]

I'm having a similar problem here, so I thought I had found my answer right off the bat in these series of posts. Truck cranks up fine when cool, so I'm thinking flakey electronics. Replaced TFI, no change; truck still dies after about 10 minutes. I can hear fuel pump on the rail do its thing for a couple of seconds even when the truck is warm. No visual evidence of gas in the fuel pressure regulator vacuum tube; very, very slight smell of gas in the tube- I could be confusing the rubber boot smell. Installed a gauge to the schrader, 32 psi at idle. As the truck is about to shut down, pressure falls to 10 psi as it is stalling. The pressure starts falling right before you start to notice a drop in engine rpm. I can still hear HP pump running for 2 seconds after engine dies. Exhaust smells rich like engine was flooded. Depending on how hot the engine is, it may crank back up immediately, or I may have to wait a couple of hours before it starts again. Does this still sound like a fuel pump? Which one?
Thanks!!

Did you ever figure out your issue? I’m having the same problem