Fuel Related Issue at Start Up

[itsaguything]

Also, I concur with @jlglr4 , those values are not consistent. Are those OE (original equiptment, LR branded) replacement sensors?
(Yes the distinction... OE ensures LR specifications are folllowed. OEM merely means its the same manufacturer but not necessarily the same specs adopted.)

 

[gsxr]

Also, I concur with @jlglr4 , those values are not consistent. Are those OE (original equiptment, LR branded) replacement sensors?
(Yes the distinction... OE ensures LR specifications are folllowed. OEM merely means its the same manufacturer but not necessarily the same specs adopted.)

+1.

What brand sensors were installed, and what vendor were they purchased from?

 

[itsaguything]

Its interesting to read the number of those who install bits from alibaba, or similar... then go back and swap them out for OE, and discover everything now works.

I recently read in another forum
1. where the subscribers were complaining of the lack of interoperability between LR (QA'd) components and the aftermarket junk that is available.
2. But my favourite is where the user wanted to hack the ECM to accommodate a generic cheap replacement component from you-know-where. Jeepers.

 

[rubbndubbn]

I don’t think the problem is the PVC.

I agree with you on this as well. Just was so cheap to do so thought I might as well do it.

0 psi desired at 650 rpms,

This was after letting off the gas... would that make any difference? Not asking for any fuel as it comes down after being revved up?

then the same 1450 psi desired at the next three rpm levels. And the actual rail pressure stays pretty similar at the first three rpms, and drops to 42.1 at the last.

The three pressures that stay the same are is after it idles out on initial start up and Im giving it gas to rev up. The 42.1 is on start up. Thats the right as Im pushing the start button so Im guessing pressure has gone down while not running and sitting for a couple hours?

You mention that both sensors were replaced - I assume you mean the low pressure sensor and the rail pressure sensor. That would have been my first guess. Could be a wiring issue someplace with those strange zero readings. I’d look around for evidence of rodents anywhere in the engine compartment - bit wires obviously, but also little food scraps, nut shells, ****. Also, if you had a sunroof drain problem that caused any flooding in the passenger side in the past, maybe some corrosion is creeping up.

Honestly this has been a very high topic of conversation I have had with my father-in-law. Is it possible? Very I live rural so mice are everywhere. I have searched high and low for any sort of wiring being chewed... cant find anything but lets be honest there is like 20 miles of wiring in the engine bay alone haha. I also cant see the wiring running to the HPFP unless I was to remove the linear to get a clear look at it. If I was to go that far Id order the pumps in prep to replace them and if the wiring was chewed Id fix that first.

I think HPFP would be my next guess. As I understand it, the fuel pressure regulators are built into the pumps - I think it uses pulse width modulation signals from the ecm to determine how much fuel to deliver with each ****** of the pump. If the regulators are no longer working, the rail pressure will not be adjusting giving you sometimes more pressure than desired and other times less pressure than desired. Moreover, if the car can detect that it’s not able to control the regulators, maybe it’s defaulting to some kind of scheduled desired pressure. I don’t know - I’m guessing. Again - could be the wiring to the HPFPs rather than the pumps themselves.

I think I am going to take it to a shop to see if they can diagnosis something better than what I can. I will do the pumps on my own but if they think its something else Id rather do what they come up with. I know they can throw parts at things just like I can but hoping they are able to find something better than I can.

@rubbndubbn . And battery capacity test is irrelevant unless, the battery is cold, and resting for a 6 hour period. (The very same process used at any reputable dealer) But glad to see following a complete charging it holds 12.6v after a 24 hour rest. Correct, your battery is good.
FWIW, an automotive battery can not ever maintain 15v. You are reading the charging voltage which is not the battery voltage.

Cheers!

@itsaguything Im on the same page I think I can rule out the battery. I know the battery wasn't at 15V but what it was being charged at while running just wanted to see if my gap tool was actually getting the right voltage which it was. Battery is sitting on the trickle charger still just to make sure its fully charged.

 

[rubbndubbn]

+1.

What brand sensors were installed, and what vendor were they purchased from?

High Pressure Fuel rail was genuine Bosch

Low pressure fuel rail was no LR but did have the same part number and a FOMOCO symbol but I was skeptical about that one.

 

[TimVZ]

High Pressure Fuel rail was genuine Bosch

Low pressure fuel rail was no LR but did have the same part number and a FOMOCO symbol but I was skeptical about that one.

FOMOCO is Ford Motor Company. Interestingly enough, I've found other sensors, etc. in the LR4 are marked FOMOCO. Camshaft and Crankshaft position sensors were the latest that I discovered. Can't remember off hand some of the others that I've seen.

 

[rubbndubbn]

FOMOCO is Ford Motor Company. Interestingly enough, I've found other sensors, etc. in the LR4 are marked FOMOCO. Camshaft and Crankshaft position sensors were the latest that I discovered. Can't remember off hand some of the others that I've seen.

Very true! Here is a picture of the low pressure sensor side by side the factory one. You can see they look similar but not exactly the same. That’s where I was skeptical.

I did buy it off Amazon too as I wanted it asap in hopes to get my wife’s vehicle on the road sooner. Well that didn’t work out. I sure hope it was the right sensor and not the wrong one and my choice to go through Amazon for the quick fix isn’t what is screwing me all along.

In my research I actually found that part number for this sensor is actually the same sensor for the ecoboost from ford as well. Of course if you search land rover and this part number the sensor is anywhere from $30 to $50 for that sensor. If you search the ford ecoboost and that part number I saw it as low as $10. I found that interesting.

@gsxr I noticed your sensor look different than the ones I have. You had a clear/yellowish sensor housing and you also had an additional hole on the copper part. Also your bevel on the inner lip looked more like my factory one then what my new one had. I didn't think it would make much of a difference. What your take on that?

 

[rubbndubbn]

Well I threw in the towel and took the LR to a shop to have it looked at.

They came back with saying it was out of timing at the fuel pumps and vacuum pump.

They quoted me $6000 to do the job which was replace HPFPs, Vacuum pump and to put it back in to "time".

I'm struggling with this diagnosis honestly because to me if it "jumped" timing wouldn't you want to replace that chain and I do realize this is not the same as the timing chain its the auxiliary chain which when I did the timing a few thousand miles ago "didnt" need to be replace. I would hate to do this job to then have the chain jump timing again. They told me that what they think happened is one of the pumps seized up temporarily causing it to jump.

If anyone has advice on this chain issue I'm all ears. I have read little bits here and there about it but still digging around for info on it. I kind of feel like they are just throwing a ton of parts at the car in hopes its one of the issues. Just my .02

Im getting to the point where I may just make the car a lawn ornament for a while and tackle the job myself when I have time. Im $10k in to work on this in the last 6,000 miles that is work done by me and a shop. Also to add some fun the alternator was on its way out and went from 15v charge to 11.3V charge when I got to the shop so I also have that ordered to replace which Ill do in the shops parking lot when I get there so I can make sure I get home.

 

[jlglr4]

I think I’d start by just replacing the HPFPs and see how it runs. Replacing the pumps looks to be a pretty easy job - not so much the timing on the pumps, but they might be fine. Vacuum pump is an easy replacement too.

As for the alternator, you are aware that it’s a variable output, right? As your battery reaches full capacity, it reduces the output (to my understanding). Might still be malfunctioning, but I think a bad battery can also make it behave strangely.

 

[rubbndubbn]

@jlglr4 I was told by the shop the alternator was toast. Honestly I didn't think it was based on what I was seeing on the drive. Honestly it's got 100k miles on it and it's relatively cheap anyways. I'll recheck it but if I do the pumps I have to pull the alternator. No way I'm paying someone to do the hpfp to easy of a job to me Honestly. The timing thing I have no clue about and going to be doing more research on that. Thanks for your advice.