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One call a/c
12-06-2014, 10:09 PM
Hello everyone.
Have had some issues with a fuel rail pressure codes for a few months. Key cycles reset and sometimes it runs perfect, others little acceleration and 2800 rpm max with pedal to the floor. I have an autel 802 which seems to cover a lot of the complex modules. So today I was monitoring the live data of the fuel rail pressure and I witnessed the pressure go from 18,000 psi to 0.0 psi. Then after a few seconds it goes back to normal. My question is what sensor is actually showing the rail pressure, the one on the front of the rail or the solenoid on the back ??


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NelsonSprinter
12-06-2014, 10:52 PM
To my knowledge the front is the pressure sensor, the rear is the pressure control regulator/solenoid

random
12-07-2014, 02:06 AM
As you know i have been watching my rail pressures also. As far as I know, it should not drop to 0, the van would do far more than a mild LHM, it would totally quit. In fact, to drop to zero would take several minutes of engine being off. So this makes me suspect your fuel pressure sensor(front of rail). Get more advice before you spend the money, but that my 2 cents.

One call a/c
12-07-2014, 04:37 AM
Thanks random. I plan on it. Don't wanna throw parts at it. Especially expensive ones at that. I looked at the harness to see if there were any cuts or wear but couldn't see any. Could be the sensor. But seems unlikely though. I'll just keep plugging.


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One call a/c
12-07-2014, 04:49 PM
http://tapatalk.imageshack.com/v2/14/12/07/97fa990e92646542ebad62c42aa16828.jpghttp://tapatalk.imageshack.com/v2/14/12/07/8a397469cc1ce15b134012f6790feea6.jpghttp://tapatalk.imageshack.com/v2/14/12/07/3155580064ad19188abbe2a99190e110.jpg


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One call a/c
12-07-2014, 04:53 PM
In the third picture where it just shows the four sensors being monitored the FRP is around 45,___ psi at that rpm(idle) and it's showing 7 +. Now after I turn the van off and start right back up it goes back to the 45,000 psi at idle. I'm thinking the sensor is toast.


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One call a/c
12-07-2014, 05:10 PM
Trying to upload the video with the graph but it's not letting me saying upload failed network error 😒


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One call a/c
12-07-2014, 06:17 PM
Ok. I had the scanner in hand while checking out the sensor/ plug / wiring ect. I started the van and the fuel rail pressure was normal to start. I started wiggling the plug and wiring nothing changed. So I unplugged the sensor on front of rail and the engine rpm spiked for a sec and went back down. The scanner showed 21,--- psl frozen on the graph. So I plugged it back in and the graph started to show the psi reading again BUT now the reading is HIGHER like when I start having issues while driving. Basically when my problem arises with the slow acceleration 2800 RPM Max the PSI of the fuel rail is normally higher on the scanner then normal. So when I unplugged the sensor, and plugged it back in the reading was higher than normal. My question is where does the fuel rail sensor on the front of the rail get its power from. Is there power at this sensor at all? I'm trying to determine if the sensor itself is the problem or if it's loosing power/connectivity from somewhere ???

Aqua Puttana
12-07-2014, 09:34 PM
5 vdc

64466

64467

vic

One call a/c
12-08-2014, 09:59 PM
Does anybody know if the fuel rail sensor is measured differently than the fuel rail solenoid I get psi on the fuel rail pressure sensor and I'm not sure if that fuel rail solenoid is measured and bar any clues or ideas?

Today I plug the scanner and when first starting up the sprinter taking it for a drive I had immediate PSI zero out intermittently got to my destination about 30 minutes away turned it off another 15 minutes 20 minutes started it back up everything's fine no problems. Turned it off turn it back on no problems everything's fine beginning to wonder if the sensor issue is when happening when it's cold rather than warm? at a loss

I'm wondering if a sensor could fail like that intermittently and then cycle the key and it be fine or if there's an ECM problem?

Or could another sensor cause me to get a zero psi reading it doesn't seem likely the scanner live data is measuring or at least monitoring the PSI output of that sensor and four to go to zero that quick and then go back to normal its boggling


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One call a/c
12-08-2014, 10:18 PM
http://tapatalk.imageshack.com/v2/14/12/08/c5abcd245d68ac065539bc104485dc1d.jpghttp://tapatalk.imageshack.com/v2/14/12/08/d4847f72532775b93cda5f5f0b24bc63.jpghttp://tapatalk.imageshack.com/v2/14/12/08/04253cd40a3a8d9b16dd9d369357f0e1.jpghttp://tapatalk.imageshack.com/v2/14/12/08/e10918cffba55a7990618a3a789851cc.jpg


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One call a/c
12-08-2014, 11:37 PM
Think I should just go for the front rail sensor ??


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One call a/c
12-09-2014, 01:16 AM
Hey random. Did you ever find out what was causing your fuel rail code ?


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random
12-09-2014, 01:53 AM
Well I think it is the solenoid. I have another one on the way now. Did you test yours?

One call a/c
12-09-2014, 01:59 AM
Yeah. Nothing got by it on the leak-off test. Injectors are good also. There's something going on with the rail sensor on the front or the ecm.


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One call a/c
12-09-2014, 02:02 AM
When it's acting out , I can get the live data to show it zeroing out as im driving and sometimes when I press the pedal fast. Then I can shut her down , start back up and everything is perfect. No crazy live data reading, great power , no problems. I am suspicious if this problem is happening after the van is sitting for a while either overnight or for a good amount of time I'm going to keep an eye on that before I order a rail sensor


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One call a/c
12-09-2014, 02:35 AM
random, have you monitored your rail pressure while driving? What kind of readings are you getting ?


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One call a/c
12-09-2014, 03:39 PM
Anyone??


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random
12-10-2014, 12:57 AM
random, have you monitored your rail pressure while driving? What kind of readings are you getting ?


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I get about 350 or so bar at idle then up to 1350 or so before it goes into its LHM thingy.
You should never see a 0 reading like you got.

One call a/c
12-10-2014, 02:23 AM
Yeah. I never see zero when in the mode your seeing bar. That is normal. It's in the obdll mode then live data is when I see the psi reading of the rail. That's when I see it go to zero and kick me into LHM or fuel related LHM. I can clear the code while driving and I get my power back unless it sees zero again. I did that today while taking an hour drive to a job.


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One call a/c
12-10-2014, 02:57 PM
I need to figure out how/ where the wiring for the front sensor is ran so I can look for any opening or shorts. Ordered a new sensor too just in case


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One call a/c
12-10-2014, 07:10 PM
Got the new sensor in, took it for a drive cold, numbers are looking good. Ran perfect with no drop out on the live data. I'll keep an eye on it for the next few days and report back.







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One call a/c
12-10-2014, 11:46 PM
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random
12-11-2014, 02:38 AM
Hey that's good news! Still running well?

One call a/c
12-11-2014, 02:43 AM
So far, not a glitch. When I'm monitoring the fuel rail sensor I'm in the obd mode live data. Not the scan mode. Scan mode shows bar? Obd mode psi for the sensor. The bar reading may be for the rail solenoid sensor though. Not sure. But looking promising


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One call a/c
12-11-2014, 02:45 AM
Did you order the solenoid only or the complete rail?


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One call a/c
12-11-2014, 02:47 AM
I noticed they sell the solenoid by itself on eBay. Not sure why if it's not serviceable ? It shows for 04-06 too ?? Maybe once you install, you can't remove without replacing ?


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Aqua Puttana
12-11-2014, 02:58 AM
... on eBay. ... It shows for 04-06 too ?? ...

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I've seen O2 sensors listed on eBay for 2002 - 2006 Sprinters. I find that interesting comical because the NAS aka NAFTA 2001 - 2003 OM612 engines don't even have an O2 sensor.

Maybe you can just replace the solenoid, but don't ever automatically assume eBay or any other general parts listing is a 100% correct reference source.

:2cents: vic

One call a/c
12-11-2014, 03:00 AM
That's true. And I did check the part number which matches the one on mine. I thought that was weird but,


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One call a/c
12-11-2014, 07:31 PM
Day 2. Vans running like a champ. It was a bad fuel rail pressure sensor after all. The one on the front of the rail. Feels good knowing all is well. Next is to DARF the tranny. I have mild rsn and may drill it with a smaller bit. Just changed the fluid a few months ago. Probably just empty the sump and reuse


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bnever
12-23-2014, 04:53 PM
Do you happen to have the part number for the sensor? Is it easy to change?

random
12-23-2014, 08:59 PM
Bnever I sent you a pm.

random
12-23-2014, 09:03 PM
Oh and one call, ifyoure still watching this, I call bs on the solenoid test. All 3 rails and solenoids i have flunked it, and the one that flunked it worst was the best runner.??

One call a/c
12-24-2014, 02:04 AM
My test was done without any fluid return. Injectors and solenoid. I personally didn't think it would have made a difference. But then I guess that is why you and I are here. We're not professionals when it comes to the all mighty sprinter. Merry Christmas


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blfmtriv
12-25-2014, 12:26 PM
Hi random I too would be interested in a part number, I think this post has answered my own problem , thanks andrew

One call a/c
12-25-2014, 05:01 PM
This is the one I bought. Working flawlessly
http://tapatalk.imageshack.com/v2/14/12/25/ae442a24a862f1cbfadc8fe19ddd299c.jpghttp://tapatalk.imageshack.com/v2/14/12/25/a5377d9759289dc2c90cc26eac54e745.jpg


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One call a/c
12-25-2014, 05:43 PM
http://tapatalk.imageshack.com/v2/14/12/25/774832b2fe67fcf82cda1e627d868c47.jpg


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One call a/c
12-25-2014, 06:08 PM
Simple to change. Just make sure the vans off for a bit first so the pressure bleeds off. A little fuel comes out. Very little. Didn't use anything on the threads either. The original didn't so I didn't


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