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I’m working on a 1997 Ford e350 clubwagon. It’s 2wd, auto with a gasoline powered v8. It won’t start. When my pastor called me, he said the fuel pump was out and asked me to replace it. I assumed he had it tested to confirm that, so I pulled the tank and replaced it, the pickup strainer, filter and straps in 12 below weather. Still won’t get gas. Pump is not spinning. Replaced the battery since it tested bad. Cranks over in park like a champ with 950 CCA battery! But still no gas. I tightenned the shifter bracket screws that were loose, still no gas. It will not crank over in neutral. I have not done various tests due to bitter cold, but now that it’s above freezing I’m at it again. My instincts tell me the nsss or the shifter cable is bad. What and how would any of you guys test first? I’m a retired auto body man with more than a little experience, but I’m not too proud to admit that I’m stumped. Please help!
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About getting no fuel:
Have you checked the fuel pump relay and fuses related to the fuel pump?
I am not sure if Fords work using a crank position sensor or camshaft position sensor, but here is generally how a fuel pump system works.
When you turn the key, the fuel pump runs for a few seconds to ensure the system is primed, then shuts off. When the vehicle is started, the crank rotation sends a signal from the crank position sensor (or cam position sensor) to let the ECU know that the engine is turning and should get fuel delivered (turns on fuel pump)…. If this signal is not sent, then the fuel pump will not run…(a safety feature) so gas does not keep getting pumped in case of an accident, etc…
So you could have a bad Crank position sensor (CKP) or Cam position Sensor (CPS)…
Will it still crank in park? If so, fix the fuel issue first….
Also, have you tried jiggling the shifter when it is in neutral while turning the key? You may have a range switch out or as you think, it could be out of adjustment…
-Karl
I did the gear selector jiggle thing in neutral, no cranking. Cranks over like a champ in park, but no gas flows. I swapped out all the relays and triple checked all fuses under the hood and in the cab, all good. Also, no trouble codes to read at all. I wonder if the crank sensor can be checked without removing it? I was going to get a can of starter fluid and spray it in while it cranks to see if that will get something going later today too.
Yes, another roundabout test of the fuel system not working is to see if it starts with starter fluid.
This may help too…
http://troubleshootmyvehicle.com/ford/4.6L-5.4L/how-to-test-the-crankshaft-position-sensor-2
-Karl
When you turn the key, the fuel pump runs for a few seconds to ensure the system is primed, then shuts off. When the vehicle is started, the crank rotation sends a signal from the crank position sensor (or cam position sensor) to let the ECU know that the engine is turning and should get fuel delivered (turns on fuel pump)…. If this signal is not sent, then the fuel pump will not run…(a safety feature) so gas does not keep getting pumped in case of an accident, etc…
I don’t know what car does that, but that’s a terrible system.
Here’s my understanding of the two common systems:
Return style: Pump runs whilst ignition is running continuously, and a vacuum regulator returns more fuel back to the tank by the return hose when engine load is low, and when engine load is high, the return line is ‘restricted’ to increase pressure behind the injectors.Returnless style: The pump spins up and as pressure increases, the speed is reduced. The pressure is built up in the rail.
The terrible idea in your comment is that the pump would be cycled like crazy, intermittent running of the pump like that would be generating heaps of electrical noise, and probably heat if they use a circuit that is intended for solid state switching.
Looking at the circuit diagram for my car (obviously won’t be typical of all):
Fuse from ignition switched source, goes to ECU (stall would of course show as 0 RPM, no speed, etc). The ECU completes the circuit to ground for that fused circuit. This fused circuit controls two mechanical relays. The relays are just the typical mechanical relay (they don’t like being cycled often, they will fail).Two relays, the output of relay 1 goes to relay 2 (safety in case one relay fails on). I know the setup my car shipped with is a return style system hence the pump runs continuously – probably not the most efficient setup – the Mitsubishi engineers got lazy,
[quote=”mrmackey” post=130102]
When you turn the key, the fuel pump runs for a few seconds to ensure the system is primed, then shuts off. When the vehicle is started, the crank rotation sends a signal from the crank position sensor (or cam position sensor) to let the ECU know that the engine is turning and should get fuel delivered (turns on fuel pump)…. If this signal is not sent, then the fuel pump will not run…(a safety feature) so gas does not keep getting pumped in case of an accident, etc…
I don’t know what car does that, but that’s a terrible system.
Here’s my understanding of the two common systems:
Return style: Pump runs whilst ignition is running continuously, and a vacuum regulator returns more fuel back to the tank by the return hose when engine load is low, and when engine load is high, the return line is ‘restricted’ to increase pressure behind the injectors.Returnless style: The pump spins up and as pressure increases, the speed is reduced. The pressure is built up in the rail.
The terrible idea in your comment is that the pump would be cycled like crazy, intermittent running of the pump like that would be generating heaps of electrical noise, and probably heat if they use a circuit that is intended for solid state switching.
[/quote]TO ABOVE
Before you make comments on Electronic Fuel pump systems… Perhaps you should read up about them… Most use Crank signal, coil signal or Cam position sensor signal to ensure the vehicle is running (or cranking) above 300-400 rpms before the fuel pump is powered..
Less likely to look ignorant commenting on something you obviously don’t know about on a system which you call a “terrible system” and my “terrible idea in your comment” which in fact is used on a majority of vehicles…. Even Mitsubishi…
http://www.justanswer.com/mitsubishi/58ra6-mitsubishi-eclipse-spyder-mitsubishi-eclipse-2-4.html
From the above:
“My concern at this point would not be so much about the fuel pump not coming on, but that you are not getting injector pulse either.
The fuel pump will only power up if RPM signal is detected in the PCM. Similarly, if there is no RPM signal, your injectors will not fire either. If the fuel pump relay is bad, you will still get injector fire (just nothing will come out); same goes for the module.”-Karl
Actually, every auto that I’ve worked on and owned will start the fuel pump for a bit when the key is turned on, that’s normal. This van used to do that too, but does not now. Fords (love them or hate them) use a lot of safety features for the occupants and for motor longevity. They have a fuel pump cut off inirtia switch that sometimes has to be reset if there is an impact. I checked that too BTW, that button was already down. Chevy does not have that feature. I removed parts off a c5 vette that caught fire after a head on collision that killed both occupants. Even the wires for the seats melted away as did the engine intake, valve covers and tons of other stuff in it. Some Ford owners get pissed if the gas stops flowing if they hit a curb or take a speed bump too hard because the engine dies then they have to push the inirtia switch back down. At least the Ford won’t squirt fuel on an already burning vehicle.
I THINK this is the right wiring diagram for your van, if not, well, we tried. Seems the schematics for these vans are hard to find.
New info today guys. In neutral, but almost clicked over into drive, it started cranking and even nearly started and I heard the fuel pump spool up. I took the neutral start safety switch off, there are maybe one or two detents when I turn it with my finger. New nsss going in as soon as the owner gets the cash for it. I’m thinking now that will start it. I will update soon.
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