2018 F150, 5.0L Extended Crank Time

Added: 2026-05-15

[00:00:07]Well, good afternoon viewers. Today we have a 2018 F-150 4x4 with a 5 L V8. And the customer's complaint is extended crank time if it's sat for several minutes. Now, it's sat since last night.

[00:00:25]And I'm going to turn the key to crank and see how it starts.

[00:00:38]That was fuel rail pressure.

[00:00:41]Wonder if it has low side fuel pressure.

[00:00:44]It's got low side desired fuel pressure.

[00:00:48]All right, this thing started fine, but I had cycled the key to look at data.

[00:00:54]Let's see if it shows low side fuel pressure.

[00:01:02]So, this would be GDI if it has high pressure fuel pressure. Let's see what that pressure is.

[00:01:08]600 522. Yeah, that's GDI.

[00:01:14]Come on, Snap-on. We need a keyword search. Low side fuel pressure voltage.

[00:01:21]Low side fuel pressure in PSI.

[00:01:28]So, let's shut it off and turn the key back on and watch the fuel pressure.

[00:01:38]Oh, damn. Lost communication cuz I turned the key off.

[00:01:45]165 PSI.

[00:01:54]Fuel level, fuel pump, fuel pump relay, fuel pressure in PSI, that's 345. That's dropping pretty quick.

[00:02:06]It shouldn't have dropped that quick.

[00:02:08]Might have a high-pressure fuel leak.

[00:02:13]Now, it was at the dealer and they told him he needed a starter because of battery cable at the starter is corroded, but they might need starter cable connections or something done, but that wouldn't cause an extended crank time before it's firing up.

[00:02:29]Fuel rail. Fuel Fuel system monitor.

[00:02:46]Did I miss it?

[00:02:53]Low-side fuel pressure voltage, low-side fuel pressure.

[00:03:01]Yeah, it's dropping off pretty fast.

[00:03:05]Started out at 67 and now it's down to 49.

[00:03:14]Let's try starting it now.

[00:03:27]Well, I'm going to bring this in the shop.

[00:03:30]So, this appears to be dual injection cuz it has conventional port fuel injectors on the top of the intake.

[00:03:37]And it has a data parameter here indicating the percentage of total fuel mass to be delivered by direct injection. And right now it's at zero, so it's running on port fuel injection at an idle.

[00:03:50]You notice the high-pressure fuel is is climbing. That's because the fuel is trapped in the fuel rail on the high pressure side and it's expanding cuz the engine is warming up.

[00:04:02]I noticed while it was idling it turned on the high pressure direct injection injectors for a fraction of a second to relieve the fuel pressure or just to fire them.

[00:04:17]I don't think I can command this to run in port versus GDI with the Snap-on scan tool, but I don't know. I haven't tried.

[00:04:27]Uh the fuel pump duty cycle is at 33% and the low pressure fuel pressure is 66 PSI.

[00:04:38]Let's let it run for a few minutes.

[00:04:40]Let's see what the temperature is. 159° F.

[00:04:46]Desired rail pressure on the high pressure side is roughly 400 PSI and it's at 1223.

[00:04:55]I remember the first time I saw that I thought there was something wrong with the scan tool, but that's because like I said the fuel is not being injected on the GDI side.

[00:05:04]So, the fuel pressure increases cuz the fuel is basically trapped in there and is expanding.

[00:05:10]Let's let it run for a few minutes.

[00:05:14]So, the fuel pressure on the high pressure side is 1555 and the engine temperature is 175° F.

[00:05:23]So, I'm going to shut the key off and turn it back on quickly. Hopefully, we don't lose communication.

[00:05:36]Okay, I turned the key back on.

[00:05:41]And we see the low side fuel pressure decaying fairly quickly.

[00:05:59]So, that would likely be cuz this is a returnless system.

[00:06:03]So, that would likely be a a faulty check valve in the fuel pump in the tank.

[00:06:11]Now, the high-pressure fuel pressure is holding pretty good. But, if anything, this should actually increase because the engine's going through a hot soak.

[00:06:24]What did it do? It just ran the fuel pump.

[00:06:28]That's interesting.

[00:06:32]It ran the fuel pump, the low-pressure fuel pump. I heard it go buzz.

[00:06:36]You can see it commanded it on.

[00:06:44]Hmm.

[00:06:53]So, I'm going to let this thing sit for a few minutes.

[00:06:59]The high-pressure fuel pressure is holding, but the low-pressure fuel pressure is is dropping. It It went up to 80 pounds.

[00:07:10]Let's see if it runs it again.

[00:07:14]Cuz maybe with the key on, it will try to maintain it at a preset level even though the engine's not running.

[00:07:23]I've never seen that before.

[00:07:27]You wouldn't normally sit with the key on. I got a battery charger on it. Let me make sure that it's outputting voltage.

[00:07:36]Turn the fan on to cool the battery charger.

[00:07:40]It's putting out 25 amps. You see the voltage is 13.5. I don't want to the battery voltage to decay while I'm doing this. I'm just curious as to whether it's going to run that fuel pump again.

[00:08:02]I'm 99.9% sure this is a returnless fuel pump or fuel system. So, that means the only way the pressure can decay is if it externally leaks, which would result in a fuel smell or if it leaks back through the check valves in the fuel pump.

[00:08:21]Let's let it sit for a while.

[00:08:24]So, it's been about 5 minutes and interestingly, the low pressure fuel pressure is actually dropped to 60.

[00:08:33]And now it's gone back up to 66.

[00:08:37]That's interesting.

[00:08:39]But, the high pressure fuel pressure has decayed to 1474.

[00:08:45]Hmm.

[00:08:46]I don't think it's got a high pressure fuel pump leaking.

[00:08:52]Let's have a look here at the system.

[00:08:57]Okay, you can see the high pressure fuel pump on the middle of the right valve cover there and the low pressure fuel line going into the port fuel injection rail here.

[00:09:08]That's it there.

[00:09:11]I think we need to check some case histories and TSBs.

[00:09:18]So, it's been about 15-20 minutes, but I've had the key on. I haven't heard the fuel pump supply pump run.

[00:09:26]The low side fuel pressure is actually increased to 79 PSI and the high side fuel pressure is dropping. I had to rebuild my custom data list cuz I exited out.

[00:09:37]I just want to start it and see how it starts.

[00:09:50]It seemed to crank a little longer than normal.

[00:10:01]Let's see what if if the GDI system is running or not.

[00:10:11]It was.

[00:10:14]Now it's gone back to PFI.

[00:10:17]So I'm going to shut it off and turn the key back on.

[00:10:38]Mhm.

[00:10:46]Now it's dropping on both the low pressure side and the high pressure side.

[00:10:57]Wish we had a quick way of putting a shutoff valve in the fuel line.

[00:11:13]Well, I'm going to turn the key off.

[00:11:21]And while I'm letting it sit, it's 10:00 to 1:00.

[00:11:31]I'm going to check case histories.

[00:11:34]So, I loaded [music] the vehicle in Identifix and I did a keyword search for extended crank.

[00:11:41]And there's a few cases here, but I can't see [music] anything similar to this one. This one says hard to start after a fuel tank refill, so that's probably a purge solenoid.

[00:11:52]Hard to start mainly during cold mornings and appears to run rich. Well, that's probably incorrectly learned flex fuel. I checked it, it's at 9%.

[00:12:04]Hard to start and misfires for a short time after startup.

[00:12:08]Uh leaky injectors, GDI injectors.

[00:12:14]Extended crank time before it starts and after starting it sets camshaft position sensor codes 340, 344, 345, and 349.

[00:12:24]That's not our situation.

[00:12:26]Intermittent stalling. He's never complained about it stalling. He said it runs fine, it's just extended crank.

[00:12:35]Hmm.

[00:12:37]Maybe I'll try searching for hard start.

[00:12:49]This morning I cycled the key a couple of times while I was looking at data parameters and that would have primed the fuel pump cuz it actually started pretty good.

[00:13:03]Hard to start mainly during cold mornings, hard to start misfire short time, extended crank time before it starts, camshaft codes, intermittent stalling.

[00:13:15]No.

[00:13:16]Isn't that special? Well, I'm going to do a little bit more reading.

[00:13:21]So, I it sat for about half an hour while I'd read some cases on it. I couldn't find anything except for a potentially low fuel pressure from the pump. And look at this.

[00:13:32]I started it again. It cranked about maybe 3 or 4 seconds before it fired.

[00:13:39]And then I shut it off, and look at the fuel pressure on the low side. It's down to 10 psi.

[00:13:46]And the fuel rail pressure is dropping.

[00:13:49]The high pressure fuel [music] pressure is dropping. Now, is that a a check valve in the I wonder where that fuel rail [music] pressure sensor is. I think it's Well, the fuel rail pressure sensor be on the fuel rail, but the low pressure fuel pressure sensor, I wonder if that's on the port fuel rail.

[00:14:13]Theoretically, if I crank it now, it's going to crank longer than normal.

[00:14:22]Does this run the fuel pump when I open the door?

[00:14:26]Some Fords run the fuel pump when you open the door.

[00:14:46]Look at how fast that fuel pressure drops off now.

[00:14:49]It wasn't doing that earlier.

[00:14:55]And the high pressure fuel pressure drops off.

[00:14:58]So, I think I'm going to call the in-tank fuel pump.

[00:15:08]So, the high pressure fuel rail pressure sensor is on the back of the left side fuel rail.

[00:15:16]Item number four in this diagram.

[00:15:19]But the other fuel rail pressure sensor says it's right here.

[00:15:28]Had to answer the phone there.

[00:15:30]So, as I was saying, it shows the fuel rail pressure sensor right there.

[00:15:40]That's on the front of the engine, but I can't see it. So, I'm going to look up the procedure to replace it.

[00:15:47]So, the procedure to replace it says to remove [music] the foam noise insulation from the left frame rail or fuel rail.

[00:15:55]And it's threaded in about 2/3 of the way back on the fuel rail. I've actually found it. So, >> [music] >> because it's on the rail, if I take this pressure line off, if I can affix a uh a a uh shutoff valve in series in the line, I should be able to block off the fuel rail and see if it still holds pressure.

[00:16:24]So, I put a shutoff valve in the line.

[00:16:29]Make sure my fittings aren't leaking.

[00:16:30]They're not.

[00:16:33]So, I'm going to bring in my scanner over here and get it set up.

[00:16:36]And I'm going to shut that shut the truck off and shut the valve off immediately or as quick as I can.

[00:16:44]Okay, so I got a helper in the truck who's going to turn the truck off.

[00:16:50]And I'm going to shut off this valve as soon as engine stops.

[00:16:54]So, remember to turn it back on right away. Turn it off.

[00:17:02]Turn the key back on.

[00:17:09]Lost communication.

[00:17:11]You weren't quick enough.

[00:17:18]That's Here is a fuel rail pressure now.

[00:17:24]And fuel low pressure.

[00:17:31]It's holding good.

[00:17:33]So, we're going to let it sit for a few minutes.

[00:17:36]And I'm going to open that valve. Which if the fuel is going back via the Look at the how high the pressure high pressure fuel is climbing now.

[00:17:50]Cuz again, it's going through a hot soak, so the fuel pressure is trapped in there.

[00:17:55]Okay, I'm going to go open the valve.

[00:18:00]Opening right now.

[00:18:06]Okay, that pretty much confirms it.

[00:18:10]We need a pump.