Extended cranking, fuel system tests.

Tiha

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Of course warranty is not going to be easy.

Spent some time on the phone with the supplier.

Went through all the troubleshooting I have done.

All he wanted to know is the code I am getting. Which is P2291. Injector pressure low while cranking.

He says, before we swap the pump. I need to check a few things.

I hate this, I knew warranty would not be easy but that is also why I went through so much troubleshooting already.

The things he said to check, check for oil leaks. Not sure how that applies, but I have no oil leaks. He wanted me to do an oil change. I will think about that one.

VCV, which he kept calling the pressure regulator, Check, I put a new one in, he was happy with that. He said they do come dead out of the box frequently.

Wiring, I did check that and he was happy with the testing I did.

PCM, same, he was happy with the testing I did.

Now the Pressure sensor on the rail. He says I need to change it first. And of course he threw in that i should have done that already. He says that is almost always the problem. Yeah heard that before, but I hope he is right.

When I unplug the rail sensor, pressure reads 29,000 psi on the scan tool. I asked, shouldn't the truck start then? He said it might but normally no. That doesn't really make sense to me. But okay, now I have to jump through their hoops.

Maybe I will get lucky and it will run.

google found exactly what he was telling me.

P2291 is a diagnostic trouble code of the Ford 6.7L Powerstroke1. It means that there’s a problem with the high-pressure fuel injection system, and the pressure is too low. The powertrain control module (PCM) has detected an insufficient degree of oil pressure needed to control the high-pressure fuel injection system. Common fixes include replacing the pressure control sensor, getting an oil change, fixing an oil leak, and checking for issues with the gaskets.

But even more interesting, that link takes me to a 6.4 page

Another thought, this sensor is new and reads exactly the same as my old sensor. So either I would have 2 bad sensors or a wiring issue. Which I have no idea how to check yet. Need to dig into that and find a diagram.
 

Tiha

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New sensor in.

Interesting note. My 2016 reads 320 psi KOEO. New bosch sensor reads 332 psi, KOEO as well.

No change in reading while cranking, still dead.

Got me to thinking, so I put the old sensor back in. Plugged the return line to the tank. My psI went from 42 to 96 and stayed. It did this way back when I was testing before swapping fuel system. That proved the sensor and PCM are reading pressure changes.

So I said screw it, I cranked it with the return line blocked off. Thought well if the cp4 is building pressure it will probably blow a return line or something.
Nope, nothing.

I need to call supplier again. It has to be the pump.

Was thinking about throwing another PCV in it, but this is ridiculous. Can play this what if game all day.

Video with oil switch PID and new pressure sensor


 

Tiha

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It runs!

Where to start?

New pump in, It started. So it was the pump, it was always the pump.

This is the first crank after priming fuel system. I actually didn't expect it to start.

It started before the pids changed. Just an interesting note.

Now trying to figure out what useful information I can pass along. After this video I put the rest of the engine back together.

 

Tiha

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Okay trying to add something that hopefully will help someone else in the future.

I had mentioned that I read where the VCV, or FCV (the valve on top of the pump) Whatever your acronym is, That is buzzes or makes noise.

They do, 3 out of the 4 I had did make a buzzing noise. But only 1 of them was ever loud enough to hear over the fuel pump.
The others you had to wait till the fuel pump was done and the VCV stays energized for another minute or two after that.
You can hear it, if just barely and I think you can feel it.

Now another interesting point. I did not tear down any of the pumps so I cannot confirm cause, but I can visibly see the condition explained.

I had read in one place a person posted that if you loosen a high pressure injector line and fuel shoots up in the air you have a bad inlet suction valve.
Took a video and I can see a difference in the new and old pump.

If that was the cause it would certainly explain the Zero psi rail pressure. Also explains that the new pump was defective in the way my last pump failed.

I loosed the fuel line. then KOEO and took video.
I did not tighten the line or change it in anyway when I took the second video with the new CP4. Maybe not as dramatic as i expected but certainly a difference.

Here is the old, 0 psi rail pressure pump.



This is the new pump that is working like it should.

 

Tiha

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Truck is back together. I am not sure it is done yet though.

On the test drive I was getting a puff of black smoke when stepping on accelerator. I am deleted but never had that before.
Also every now and then I feel a random shake. Might be ac compressor, but I am super sensitive right now. Don't trust this thing yet.

Truck is starting pretty good. I wouldn't say it is right yet. But very close.

I think I have a lazy injector, or maybe even a fuel leak. #4 looks a bit off spec. But when I got back from my test drive #4 and #8 both were still wet. Makes me wonder if I have a HP line leak, or even a return line leak. I cleaned them off with brake cleaner and need to drive again to see.

Certainly need to put some miles on it and check again before I condemn #4.

20230827_131357.jpg


Last note, finally got my idle hours. Honestly thought it was a lot worse than this.

is that 20% idle time? Did I figure that right? Idle divided by engine hours.


20230827_153727.jpg
 

Tiha

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Thanks!

It is getting there. Finally got some road miles on it yesterday. I have 3 injectors that seem to have a little diesel seeping from somewhere. I need to re tighten the high pressure fuel line, But I think it is the return line.
Going to pull the return and replace the o-ring on those 3. Hopefully that will clear it up.
Otherwise my return harness is faulty. LOL

It starts right up. Like it should. Hasn't started that good in years. Very happy about that. It burns clean at idle even from cold start. No smoke, no haze.

But, it is not the same truck. Not sure if that is normal? Or maybe the system needs to relearn. But it drives different.

Still getting a puff of black smoke on take off. But more so it feels like it has a lot more low end off the line. Like you barely touch the pedal and it wants to go.
Then it seems like there is less acceleration than there used to be as when getting on an entrance ramp.

Have not had it on a trailer yet. Boost seems to be the same.

Like I said before I am over sensitive right now, so we will see. Have not put a computer back on it yet either to see what the fuel trims are doing. If that #4 injector is not sealing and dumping fuel that could be my black smoke. Or maybe it is just wishful thinking.

Not sure what I could have done different. I got a motorcraft kit. Spent probably more than I needed to. At this point I feel like I should have bought the cheapest crap out there for the results I have gotten. Also wondering if NEW vs reman bosch or motorcraft would have been any different.

The replacement CP4 they sent had test paperwork. The original did not. Should that have been a sign?
 

Tiha

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whats your low pressure fuel psi now at idle?
Hasn't changed. Runs 62-63 psi.

I swapped o-rings on the return harness on those injectors. If they were leaking they are not now.

Still questioning 1 injector. But no time to screw with it right now.

Thinking back, when I pulled injectors to have them tested I never marked them. I figured the IAQ number would tell me where to go if I put them back in.

The guy that tested them did not mark them either. Nor did he reference the IAQ numbers.

Would have been interesting to see his test stand results compared to the fuel trim data I had. But I have no way of knowing now.

The one injector I question. is -2.2 mg. None of my original injectors were ever that far off. 4 of them were questionable on fuel trims of half that amount.

Hasn't thrown a code for the injector yet. No idea at what point it does or what the triggers are.

That injector is in hole #4 which originally was looking really good on fuel trims, so that kind of rules out a mechanical issue in my mind.
 

lincolnlocker

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Hasn't changed. Runs 62-63 psi.

I swapped o-rings on the return harness on those injectors. If they were leaking they are not now.

Still questioning 1 injector. But no time to screw with it right now.

Thinking back, when I pulled injectors to have them tested I never marked them. I figured the IAQ number would tell me where to go if I put them back in.

The guy that tested them did not mark them either. Nor did he reference the IAQ numbers.

Would have been interesting to see his test stand results compared to the fuel trim data I had. But I have no way of knowing now.

The one injector I question. is -2.2 mg. None of my original injectors were ever that far off. 4 of them were questionable on fuel trims of half that amount.

Hasn't thrown a code for the injector yet. No idea at what point it does or what the triggers are.

That injector is in hole #4 which originally was looking really good on fuel trims, so that kind of rules out a mechanical issue in my mind.
Thats low man... id put a lpfp in it.
 

Tiha

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Thats low man... id put a lpfp in it.
It actually has the LPFP from my 2016 in it right now. And my 2014 LPFP is in the 2016.

They both run exactly the same PSI. The 2016 lpfp has 50k miles on it.

More psi would be great but I think this is the way Ford designed it.

I want to clean the MAF and MAP but eventually I need to warranty that #4 injector.

Been driving it some more. It seems to be better. Maybe I am getting used to it. Maybe the computer is relearning.
 

Tiha

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Just an update for kicks.

I almost trust the truck again. It has been running fine.

But still, have way more power off the line than I used to and it doesn't run the same on the upper end. Trying to talk myself out of screwing with it.

Haven't watched fuel pressures during a hard pull like I said I would yet but I am convinced it is CP4 related.

Interesting thing is, I am getting just a tad over 20mpg. This truck has never done that well.

So am I doing damage? I wonder. At best I think I hit 18.5 once right after deleting it. But usually averaged around 18mpg.
 

PDT1081

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Interesting thing is, I am getting just a tad over 20mpg. This truck has never done that well.

So am I doing damage? I wonder. At best I think I hit 18.5 once right after deleting it. But usually averaged around 18mpg.
Or is it finally acting correctly and wasn't before?
 

Tiha

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Or is it finally acting correctly and wasn't before?
I suppose it is possible.

My 2016 runs very similar to what my 14 used to. I actually didn't like the extra boost and shifting of the 16, but now the 16 is much nicer to drive.

If I give this truck 1/4 throttle at stop light it will snap you head back and spin the tires. Got to be really gentle with it. Pedal is touchy. Never like that before.

If I stomp it to pass someone or on entrance ramp it sounds like it is doing something and it goes but not like it used to or like my 2016 does. Which is where my extra fuel mileage is coming from I suspect.
 

Tiha

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This truck is still giving me problems. Been trying to drive it and tolerate it but it keeps popping off the fuel return line on #7 every couple of weeks. Then it is dumping fuel on the ground.

It is not like anything you notice, I get out of the truck and smell diesel fuel. Look underneath and it is dripping. Pop the hood and the return connector is sitting on the injector fitting. I retract the lock. Slide the fitting back on and lock it. Nothing looks damaged. The little oring has been replaced a couple times. I am going to put a zip tie around it tonight I think and see if that makes a difference but I bet it moves to the next weakest connector.

It is starting good. Seems to be running fine minus the total lack of top end performance.

Talking with the supplier about whether to warranty out that injector or the whole system. I have 2 other injectors that the fuel trims are way out on. He said he would just warranty them vs forcing me to have them tested first.

This was a Motorcraft reman contamination kit. I am thinking about swapping to brand new bosch injectors and Brand new cp4. He has the new injectors but does not currently have any NEW Cp4 available to him so he would give me a credit to go wherever I wanted.

I don't need the other parts from the contamination kit. It is all new.

Debate is not only what CP4 to get but maybe I should just swap injectors first? See how it runs. I have no idea. What a nightmare. I am about ready to drop it off at Ford and spend the $10k or whatever but there is no guarantees in that either. It could run as poorly as it does now and they can say, well that is in spec.
 

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