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VDO fuel sensor

vickruis

Member
I’m having an intermittent high fuel pressure warning from my AFS 4500. Fuel pressure is way too high, sometimes even before starting the engine. I suspected and cleaned the grounds with no effect. AFS warns the VDO sensors wear out as early as in 200 hours, so after 480 hours it is time to replace this one. Replacing the VDO by a more reliable Kavlico requires a rewiring, not my choice for now.
Looking in the Spruce catalogue I find that VDO warns that their pressure senders (in this case P/N 10-06581) are not to be used with any type of fuel application. Huh?
The AFS manual shows a VDO fuel pressure sender, P/N 41315…. Is this the same sensor, and does anybody know why VDO warns against the use in fuel applications? I mean, apart from the 200 hrs lifespan...
 
GRT

Many vendors use VDO senders. Yes they fail often it seems, and others get lots of time from them. I’ve read the fuel use warning. Maybe the fuel fumes damages them. The VDO brands come in various pressure measuring range... low for carbs and higher for fuel injection applications. Just replace ($50-$65) and hope all goes back to normal is my opinion. A google search for me doesn’t find the 41315 model.
 
As far as I can tell this AFS part number 41315 has the same specifications as the Spruce part number. I'm located in Europe, ordering directly from AFS would see shipping costs way higher than the cost of the sensor.
 
The AFS manual shows a VDO fuel pressure sender, P/N 41315…. Is this the same sensor, and does anybody know why VDO warns against the use in fuel applications? I mean, apart from the 200 hrs lifespan...

I think your part number is one AFS gave it. Seems all vdo numbers start 36...
 
VDO Part Number / Identifying Marks

Hi Victor,

Like you, I went through VDO pressure sensors on a regular basis. Some lasted as long as ~100 hours. At ~50 USD each, it wasn't a big expense but their reliability was poor and they seemed to start failing on cross country trips. Looks like you're running an IO-360 so I'm going to presume that you're using the 80 PSI unit. I think the VDO part number was '360-003'. Looking at the facets where you tighten the sensor with a wrench, you should see a '29/4' stamp. I used this link to properly identify the VDO part-number:

https://www.jegs.com/p/VDO/VDO-Pressure-Senders/887192/10002/-1

In the end, I ordered the replacements from a reputable online auto-parts store.


I took two of the sensors apart and the failures were different. In one, the internal resistive coil had been worn out by the wiper (presumably from the mechanical fuel pump pressure pulses). The other failure was due to an internal wire breaking where it connected to the external terminal that passes through the case.

As to your question, I don't know why the fuel warning.

Good luck to you,
 
Do yourself a favor...ditch the VDOs and spend an afternoon running one more wire for power. I went through a handful of VDOs before Dynon started selling the Kavlicos, switched over and have had zero problems with them since installing them around 600 hours ago.

"'Tis a false economy to invest in cheap goods." :) Not to mention, passengers get nervous when the systems sets off alarms for fuel or oil pressure, even if *you* know they're not a real problem.
 
Shortage of supply

Just went through this problem. Tried to buy a high pressure Kavlico. It's about 4 months out so I had to buy the VDO
You mileage may be different. I tried a half dozen vendors including Dynon.
Art
 
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Advanced Flight, Dynon, and Garmin have all sent out service bulletins this past May recommending replacement of the previous Kavlico pressure sensors with their newer, higher pressure upgraded 150 psi fluid pressure sensor due to a "small number" of leaks, including sprays. No crashes, no fuel exhaustion, no fires reported.

The Dynon/AFS part number for that sensor is 103757-000 (0-150 psi). The Garmin part number is the same as the Kavlico part number P255-150G-E4A.

People must be heeding that advice...that 103757-000 sensor is pretty hard to find...backordered most aircraft specialty stores. I didn't look at places like Allied.

https://www.advancedflightsystems.com/service-bulletin-050620a.php

https://www.dynonavionics.com/bulletins/support_bulletin_050620E.php

https://www.garmin.com/en-US/aviati...g3x-g3x-touch-equipped-experimental-aircraft/
 
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Advanced Flight, Dynon, and Garmin have all sent out service bulletins this past May recommending replacement of the previous Kavlico pressure sensors with their newer, higher pressure upgraded 150 psi fluid pressure sensor due to a "small number" of leaks, including sprays. No crashes, no fuel exhaustion, no fires reported.

The Dynon/AFS part number for that sensor is 103757-000 (0-150 psi). The Garmin part number is the same as the Kavlico part number P255-150G-E4A.

People must be heeding that advice...that 103757-000 sensor is pretty hard to find...backordered most aircraft specialty stores. I didn't look at places like Allied.

I originally ordered two of these from Aircraft Spruce to replace oil and fuel pressure sensors per the AFS service bulletin. That was on Feb 22. One was promptly sent, the other has been on backorder for more than a month, so I canceled and ordered from Allied, which appears to have plenty of them. Same price.
 
Replacing the VDO by a more reliable Kavlico requires a rewiring, not my choice for now..

How is your sensor wired? Often spurious indications are caused by a ground loop. The sensor and gauge are grounded at points of sightly different ground potential. You might try wiring both to the same ground point.
 
The VDO sender just has a single wire, and gets its ground from the airframe it is attached to. The Kavlico has 3 wires; signal, ground and a reference voltage. The ground is easy to wire. The only hard part of this wiring is splicing into the +5V reference voltage wire (usually shared with the Manifold pressure sender).
 
If you search for the new Kavlico part number P255-150G-E4A you will find lots of supply at various component suppliers like Allied Electronics.
I want to replace my oil pressure sensor which which is the same part number. The "A" in the part number denotes it comes with the electrical mating cap. How do the wires connect? Does it have pigtails that I can crimp to, or does it come with pins that I need to crimp? Basically my question is other than wire and maybe but splices, are there any other electrical components I need to order to install the sensor?
 
It's a GM Metri-Pack 150 sensor connector as available at Ballenger Motorsports. My Silverado happens to use the same connector on its OP sensor (also a Kavlico).

The "A" version comes with a pigtailed connector, but you can do a nicer installation with the crimp version above.

The datasheet for the sensor describes the pin assignments.
 
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