Ambient sensor faulty, missing connector. Check engine light, rail under/overpressure

[SneakyAnarchistVanCamper]

Well first off I need a new connector for the ambient air temp sensor. It is missing, hacked and taped up by the P.O. I'm wondering if it could cause a check engine light, a shutdown at a stoplight, and these codes:

B1471 ambient temp sensor has open or short to positive
2015-1 CEL On & Current fault - Rail pressure monitoring. The maximum fuel flow quantity was exceeded.
2047-1 CEL On & Current fault - Rail pressure monitoring via volume control valve. The maximum rail pressure was exceeded.
2017-1 rail pressure monitoring. Rail pressure is too low.

Rail pressure during 2047-1 code: 577bar/8368 psi
Y74 pressure regulator valve: 29%
Fuel tank level 48 (half full)

During a different instance of 2015-1 code:
934 bar/13,456 psi set value
Rail pressure 496 bar
Y7r pressure regulator valve 30%

According to europarts ". Although small and seemingly insignificant, this is a critical sensor, signaling outside air temp to the engine control module." -True??

I changed the fuel filter (was pretty clean upon disassembly) after I first got the CEL and the 2047-1 max rail pressure code. Plenty of power, running just fine, but then the other night after changing the fuel filter and after a 30 minute and then a 10 minute drive, it turned on the CEL (same codes as above) all of a sudden it shut the engine off at a stoplight once it turned green. Nothing on the LCD display but it was lit up, and after a few attempts to turn the key from position 0 to position three, it started up and got me home. Earlier that day, I primed the new fuel filter by turning the key to position 2, letting it sit, and repeated. But I didn't open the WIF drain. Wondering if I just introduced a bunch of air into the system, causing it to later shut down?

Dr A told me to check low side fuel pressure with a T and a pressure gauge at the filter, because these codes can often mean it's not getting enough pressure/flow, as opposed to too much (because of overshoot). I can't till the shop is open monday. I opened the WIF drain and closed it down not too tight this time, to inspect the fuel for air bubbles and contamination, neither were found, and it filled up a plastic water bottle in about 1 second. In hindsight I should have used a gallon container..

So I need to know if the ambient temp sensor could be the culprit of all this. And I'm wondering what my next step would be. I'm worried she will break down any moment. The fuel quantity control valve on the HP pump regulates the pressure going to the rail, right? My fuels instructor said the inlet metering valve aka quantity control valve on the hp pump is to be suspect- should I just replace it?

Edit: The connector ( 05120749AA ) and terminal ( 05103880AA ) are actually in the parts manual, so I'll order those. Jw if it's irrelevant or not cause I've found conflicting data.

 

[lindenengineering]

First that ambient air temp sensor IS important!
It helps determine the ACTUAL air density measurement when compared to the ambient air pressure sensor in the PCM,
Hence it affects boost and is was part of a 2004 Dodge bulletin on the matter.
You can get a gash socket from a Landrover Discovery 1 or 2 or Range Rover P38 from wrecking yard!

The AIT sensor socket is the same!

Hack n whack it off a crusher specimen and solder it to your harness !

The other faults you have are due to injector rail pressure feed monitoring and cavitation.
Fuel supply pressure or lack of it and filter condition is one issue and injector internals like excess internal leakage at high full throttle demand is another !.
Dennis

 

[autostaretx]

"Local" source of parts: https://sprinter-source.com/forum/showthread.php?t=54312

--dick

 

[SneakyAnarchistVanCamper]

It starts, runs, and accelerates great, the lp pump pumps by my rough estimation (2 12 oz water bottles in 1 second) around 8-11 gpm. So I'm thinking it's likely not the lp pump, hp pump, or injectors, more likely a sensor/valve, cause if any one of these weren't doing well, it wouldn't run well. I'm about ready to buy a flow control valve for the hp pump, as I have read this is sometimes the cure.

I did find this bit of info, having my 2017 code..
"Case Number K72904974
Vehicle Issue Potential DTCs, P2017, P2018, P2019, P2020, P2021, P2023.(2017, 2018, 2019, 2020, 2021, 2023) Intermittent stalling and or low power with or without CEL;Poor pin fit at fuel pump relay socket or defective relay for low pressure fuel pump.The loose pin fit is usually located on the RD/BK wire. The tab is usually bent where it is not locking correctly in the relay base housing causing the pin to back out of the housing resulting in intermittent operation of the low pressure fuel pump. This intermittent operation of the fuel pump causes stalling and potential operation of the CEL due to rapid changes in fuel pressure.
System or Component Engine Performance;Group 14 - Fuel System
Recommendation Check and correct pin fit at fuel pump relay to ensure proper fit on relay pins."

And for the fuel quantity valve, I found this: "
Test: Start the vehicle and count. Are erratic idle and stalling are not present for 30 seconds and then suddenly start? Restart the motor and count again. Do the the symptoms start again right at the 30 second mark? If yes, the valve is most likely the cause.


Also to note, if you are running rough/stalling within the first 30 seconds but then smooth out consistently every time after 30 seconds, the solenoid at the end of fuel rail is starting to go. The solenoid is creating erratic pressure which causes rough running."

But I don't have rough running or stalling or even unstable idle. Just the codes, CEL, and one stall 10 minutes into a drive. So... less likely it is the fuel pressure solenoid? Leaving me with the quantity control valve on the hp pump, intermittent power loss to the lp pump, or a harness issue?

Come to think of it, I did use a pressure washer under near the tank recently, I'm going to check on the lp pump connector..

I did find this fuel pressure solenoid test: https://sprinter-source.com/forum/showthread.php?t=27630

 

[220629]

...

Come to think of it, I did use a pressure washer under near the tank recently, I'm going to check on the lp pump connector..
... [/url]

Sprinters never seem to respond well to pressure washer application. In fact, I think it pisses 'em off. "Don't pressure wash on my leg and tell me it's raining."

vic

 

[SneakyAnarchistVanCamper]

Injector leak off test done today, vials only fill 1cm or less in 10 seconds cranking. Rail pressure control solenoid spits out plenty of fuel during 10 second cranking test while plugged in (35ml est.). Yet the rail pressure solenoid leaks none when unplugged. Not sure about the results of my test yet..


I got 20 feet of 3/8 clear vinyl hose. Dr a kindly took his time to explain how to test leak off at a higher RPm like 2000, because the standard leak off test will not show high pressure leak off, yet by comparing the long lines tied up in a bundle to the hood, I may find that one is returning a lot more than the other. I will perform this test tomorrow.


I drove around with my scanner on save data, with the hp pump quantity control valve, and the rail pressure solenoid on a graph. I will have to dig through the data later to try to find the point when it cut out. The CEL, triggering rail over/under pressure codes happened twice over an hour, both times, again, accelerating from a stop. And it wasn't a roaring acceleration either, just a normal one. But it didn't shut off once today, and when the CEL came on, it didn't lose power or limp or anything. I tried plenty of hard acceleration and that's definitely not a problem, couldn't get the code to happen. She revved up to 4k for the first time in my ownership that I've truly put it to the floor and it got to 60 amazingly fast.

Each time the fault occurs, the rail pressure is around 200-600 bar less than the set value rail pressure. Could this be an intermittent electrical wiring open/short?

I was not able to pressure test the lift pump yet, couldn't find the right combo of tools in the shop. Wonder if I could use this harbor freight diesel cylinder compression test gauge without ruining it.

I still have my stink eye on the quantity control valve... But I really need to know if the lp pump is cutting out or not, to separate it from a hp or lp problem. The yellow housing of the fuel pump relay does rattle when I put my finger on it, and it's a little warm..

The other codes are just glowplug codes and the cam sensor I pulled off and the pressure solenoid connector I pulled off during the test.

Come to think of it, I've got both grounds behind the headlights cleaned up, now the ground under the drivers seat needs to be cleaned up... Fuel pump relay ground source I'll bet.


"If the Actual Fuel Pressure gradually drops below
the Fuel Pressure Set Point then spikes well above
the Fuel Pressure Set Point, replace the fuel pressure
soleniod (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/FUEL PRESSURE SOLENOID -
REMOVAL), and recheck."


Edit: I took her to Mercedes Wilsonville sprinter center Let's hope they don't ream me a new one. Mccoy sprinter center was booked till next week.

 

[SneakyAnarchistVanCamper]

Looked through the saved data, it's all text; can't find where it died. And it doesn't show rail pressure or set rail pressure while monitoring both the fuel valves. The autel scanner has met its limits with this one as far as diagnostic data.

Wilsonville mercedes can't figure it out yet, and they service sprinters there.

 

[SneakyAnarchistVanCamper]

Of course, Dr. A was spot on. I should have done that high rpm leak off test before taking it in. Test performed at idle, not sure if fuel pressure solenoid was unplugged during test, will repeat. The idle leak off test that I did revealed the most fluid in #4, but #3 looks near the same as the others. But apparently this can change drastically at operating temperature and higher rpm. Not sure if I should replace the injectors myself, gambling with breaking a hold down bolt, or just let them do it, and have them pay for any mishaps. Depends on the quote.


Here's what I got from Mercedes:

"Checked low pressure fuel system pressure using a pressure gauge T'd in at the fuel filter, and found no abnormal fuel pressure fluctuations. Fuel pressure of 4.5 bar is maintained even under heavy throttle, and when fault occurs. Installed test quantity control valve on high pressure fuel pump (controls fuel flow through high pressure pump when fuel is at operating temperature), fault still occurs. Removed and inspected mechanical fuel overflow valve, no issues found with this valve. performed injector leak-by test with engine at full operating temperature. Cylinders 1, 2, and 5 have even leak by. Cylinder 4 leaks by about 20% more fuel. Cylinder 3 leaks by about 50% more fuel than cylinders 1, 2, and 5. I recommend that Cylinder 3 injector be replaced and the leak by test performed again. With an injector leaking by excessively the fuel rail pressure will be heavily affected. cylinder 4 injector may require replacement as well, and leak by of injector 4 may be much more than is currently seen once there is a properly operating injector in cylinder 3. This is the starting point for the repair, there may still be more needed to fully correct the rail pressure issue, but the worn injector(s) must be replaced first."


Here's a video of my leak off test results. #4 has significantly more, but #3 looks ok. Reverse of the results of the shops test, but my test was not performed at operating temp. My test may be innacurate due to me testing the fuel pressure solenoid at the same time (with it plugged in, instructions in manual and forums are incomplete and do not mention to unplug it). Do you think I should replace 3 and 4?

https://www.youtube.com/watch?v=ByFv3DV0VNs

 

[lindenengineering]

Of course, Dr. A was spot on. I should have done that high rpm leak off test before taking it in. I'm not sure if they performed the test at high rpm or idle. The idle leak off test that I did revealed the most fluid in #4, but #3 looks the same as the others. But apparently this can change drastically at operating temperature and higher rpm. Not sure if I should replace the injectors myself, gambling with breaking a hold down bolt, or just let them do it, and have them pay for any mishaps. Depends on the quote.


Here's what I got from Mercedes:

"Checked low pressure fuel system pressure using a pressure gauge T'd in at the fuel filter, and found no abnormal fuel pressure fluctuations. Fuel pressure of 4.5 bar is maintained even under heavy throttle, and when fault occurs. Installed test quantity control valve on high pressure fuel pump (controls fuel flow through high pressure pump when fuel is at operating temperature), fault still occurs. Removed and inspected mechanical fuel overflow valve, no issues found with this valve. performed injector leak-by test with engine at full operating temperature. Cylinders 1, 2, and 5 have even leak by. Cylinder 4 leaks by about 20% more fuel. Cylinder 3 leaks by about 50% more fuel than cylinders 1, 2, and 5. I recommend that Cylinder 3 injector be replaced and the leak by test performed again. With an injector leaking by excessively the fuel rail pressure will be heavily affected. cylinder 4 injector may require replacement as well, and leak by of injector 4 may be much more than is currently seen once there is a properly operating injector in cylinder 3. This is the starting point for the repair, there may still be more needed to fully correct the rail pressure issue, but the worn injector(s) must be replaced first."


Here's a video of my leak off test results. #4 has significantly more, but #3 looks ok. Reverse of the results of the shops test, but my test was not performed at operating temp. My test may be innacurate due to me testing the fuel pressure solenoid at the same time (with it plugged in, instructions in manual and forums are incomplete and do not mention to unplug it). Do you think I should replace 3 and 4?

https://www.youtube.com/watch?v=ByFv3DV0VNs

This is exactly how I approach this problem!
I call it the big Khauna because of the cost and frankly the only way to fit it and fix it for good is a new set of injectors at $375 a pop!
Plus 5 new hold down bolts and 2 hours of labor which includes an injector en code!
Dennis
Mechanic

 

[slowgsr]

Well worth the cost to have new injectors if needed

 

[220629]

... Not sure if I should replace the injectors myself, gambling with breaking a hold down bolt, or just let them do it, and have them pay for any mishaps.
...

I'm not so certain that they pay in that situation.

Injector bolts do break. It is not necessarily the dealers fault. I believe that the dealership solution for a broken hold down bolt is cylinder head replacement. I don't see them funding a new cylinder head/replacement. I could be wrong.

Good luck.

vic

 

[SneakyAnarchistVanCamper]

Good point AP. I'd rather break the head myself and pay for my own mistakes. I'm definitely going to do them myself, and I have a slide hammer puller. I hope they didn't fail due to fuel system contamination; you can see some fine brown rusty stuff (Rusticate?) on top of the injectors in the video. I think it's from the fuel filler neck, I may clean the tank and replace the filler neck.

I'm about to order two injectors from europarts, but I don't know if they performed the test at high or low idle. Although assuming I trust their results, which are different than mine (and performed at operating temp), I think I should order injectors asap.

 

[220629]

... I hope they didn't fail due to fuel system contamination; you can see some fine brown rusty stuff (Rusticate?) on top of the injectors in the video. I think it's from the fuel filler neck, I may clean the tank and replace the filler neck.

...

The rust dust is very typical. Contrary to what might be expected the environment under the black plastic cover can be kinda moist.

The clips that hold the plastic return fittings to the injectors are stainless steel, but the injector body is steel. The injector trigger signals are high frequency. The high frequency vibrates the ss clips against the steel creating iron powder. The moisture under the black plastic cover causes the dust to rust.

It isn't contamination. It is normal.

I added oil to my 2004 injectors wells per Talkinghorse43 because I believe that the moist environment under the cover can cause corrosion in the injector wells.

I have no data, only observation.

vic

 

[SneakyAnarchistVanCamper]

Here's a picture of MB's leak off test results, at operating temp, at idle speed. They are saying #3 is faulty and #4 may be faulty as well. It does not appear more than 1.5 inches... Should I really replace #3 and #4 injectors over this? Well, I got two coming in the mail... I will do high idle leak off test to confirm 3 and 4 are bad.

 

[lindenengineering]

For crying out loud.
What you are doing is a rudimentary test!

If like many that roll into my shop with this problem and baulk at the $1500 bill saying "OMG, I have to spend some money to fix it syndrome, then why not simply remove the whole set marking injector positions 1 thru 5.
THEN
Take them to a registered BOSCH F.I.E specialist & get them tested properly.
They should have the test equipment (it costs about $50,000!) so there will be a charge like about $250 !

This will confirm your injector health and through flow leakage rates throughout the all operating ranges, (because there is a test plan) are to spec or in need of replacement.

May I remind you all that injectors are extremely important because defective ones operating in an engine over an extended period CAN & DO wreck engines by improper injection and/or a condition known are bore washing!
It leads me to a Ist year basic diesel engine mechanics' tech course question on diesel engines!

Does the FIE system drive the engine or does the engine drive the FIE system?
Debate that to its fullest extent and you will have taken more time than you have spent fannying about with this issue !!
Dennis

 

[SneakyAnarchistVanCamper]

Oh I never mind buying and installing new parts, always worth the money to have worn out stuff replaced imo. I respect the engineering and manufacturing involved, I know it's not simple or cheap. I have two injectors coming in the mail. I will have the old ones tested and rebuilt as spares. I do understand bore washing and melting pistons. Believe me I am not being a cheapass.


What I don't understand is how my test results seem to be within spec because they are below 1.5" in 10 sec, yet they fail, due to the variation? I just looked up bosch variation and it says no more than 10%. Well I'd say 3 and 4 variate more than 10%.. I just don't see the spec anywhere in the dodge manual and no mention on the forums.

 

[SneakyAnarchistVanCamper]

Problem solved!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I replaced the rail. They were backordered in germany but https://www.moparpartsoverstock.com/ had one in their warehouse. I believe it was the rail pressure solenoid at fault, which was leaking when plugged in. Day 2 of test drives, 130 miles stop and go and no troubles so far. I mistakenly looked past the rail solenoid because it did not leak when unplugged, and I thought the literature had made an error, as the svc manual mentions to unplug the cam sensor and rail pressure solenoid for the injector leak by test, but doesn't mention unplugging either for the rail solenoid test. Whereas clearly you must unplug the cam sensor to keep the engine from starting.

So, if you have high and low rail pressure codes, shutdowns on acceleration from a stop, do a rail pressure solenoid leak test with it plugged in, and your 3/8 hose test vials on the injector return lines. If the rail solenoid leaks anything when plugged in, it's no good. There it is in plain english. I wanted to make damn sure before I spent $923 on a new rail.

I left the injectors alone. Well, at least I have two injectors waiting on the shelf for future disaster.

Edit: After two 10 second attemps at cranking, she fired right up. A couple minutes into my first test drive after replacing the rail, the CEL came on with the same codes and the engine died. I thought oh no, here we go again. Started right back up, and then 100 feet down the road did the same thing. After that, there have been zero problems. I'm really hoping it was just air in the system from installing the rail. 130 miles and 2 days of driving now, no problems.

Many thanks goes out to all who helped.

 

[dangerrose]

Did this stay fixed? I'm still trying to find the gremlin in my system...