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Discussion Starter #1
B5 2.8 liter V6 5 speed. Has anyone on the forum ever sucessfully deleted the VW "Low Oil Warning" system. It is a complete PITA in my opinion. I have great oil pressure (measured at the engine, but I keep getting numerous warnings as I drive. A new switch did not fix the issue. Want it gone and replaced with a regular oil pressure guage.
 

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Oil pressure or oil level warning? Some cars have both. Not a great idea to delete either, IMHO. If I were you, I'd just add a gauge.
 

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VERY ANNOYING ALERT. The flashing red display ALERT and HIGH PITCH ALRM TONE would still go off if I only added another gauge.

I need to stop this annoyance. There has to be a design flaw, wiring issue or a computer error that is causing this, all of which will be very labor intensive to find and replace. I'm not going to go through the expense in this older car.

The reason I want to keep the car going is that it is set up to be towed behind my motorhome (manual transmission). It also runs very nicely otherwise and has only 104k miles.
 

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Very unusual to experience spurious oil pressure warnings on the B5, with the exception of those caused by a bad ABS module. Any brake warnings? OTOH, it's quite common to experience low oil pressure after the engine is fully warmed. If you're determined to disable the warning, try disconnecting the wire to the sensor (it's a simple switch). You may need to short the wires together; I'm not sure if the switch is normally open or closed.
 

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Discussion Starter #5
Yes. I thought of shorting the wire to the switch. If Idid that I could replace the switch with a common electronic driven oil pressure swith and gauge installation. Assuming that the oil pressure closes the switch and grounds the electrical circuit to showpressure in the system, this should work. I was searching for someone else who has done this, as confirmation as a viable plan.
 

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Just making sure my assumptions are in line, in your first post you mention that you have great oil pressure, I assume you mean you put a manual test gauge to check this and have an acceptable reading ? , further on you say, "want it gone and replaced with a regular oil oil pressure gauge" did you mean you want to replace it ? or you have already replaced it with a gauge like on the dash display area? You say you get the warnings while driving do you get warnings on start up or while in your driveway? You mention B5 ,what year may I ask ? The 2.8s V6s are way easier to check than the 1.8s, but the first thing I would do is drop the lower oil pan and examine the oil pickup screen. One of the reasons I ask age is some use a pan gasket others just sealant. Although the mileage is not excessively high, the age comes into play , plastic gets brittle, things accumulate and find there way to the pan, and if not the original owner and not having a detailed history of service there is a real possibility your screen is compromised. Good news is, to do this it is maybe a 3 hour job and well within your abilities.
 

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Currently experiencing this exact same issue on my wife's 2003 V6 GLX.
Believe me, I know exactly what your getting at. That constant beeping noise, every time I pull away from a stop light. I'd rather gouge my eyes out with a blunt instrument and chew on my eyeballs just for good measure.

Seriously, yes it's annoying as hell. But something is wrong if it's happening.
My wife has been listening to this for 5 - 6 months now. I've recently rebuilt her engine so without actually checking the oil pressure, I assumed it was just fine. Besides, if it had no oil pressure the engine would be horrendously loud from all the clackity clack going on.
I originally thought the sensor was failing. When I went to replaced with a new sensor, I noticed the plug that connects to the sensor had cracked, thus leaving a questionable connection.

I've found a pigtail end from a member here and I need to install it to properly fix the problem. I'm using a zip tie around the connector now just to get me by.
98509


That wire coming the from connector is awfully small. Somewhere between 24 to 28 gauge wire.
With a wire that small, it's very conceivable that you might have hit something on the road and cut or broke the wire. It's right above the axle. Picking a plastic bag dancing around on the freeway and having that get wrapped around the axle would do it

Have you absolutely confirmed that you have sufficient oil pressure at 2000 RPM and above?
The pressure warning system won't sound off at idle with low pressure. You need to confirm pressure at above idle.
Check wiring connections and integrity. You've supposedly ruled a bad sensor.
The low oil pressure warning system is fairly robust, it just doesn't trigger the alert for no apparent reason.
Guaranteed, you've got a break or an issue somewhere in the chain.
 
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Discussion Starter #8 (Edited)
Chief, I've already been through removing the pan and checking the screen. I've measured the oil pressure with a mechanical gauge at the port where the switch screws in. Yes, the V6 is much easier than the 1.8L. My daughter has a 1,8L and I've been her mechanic. I replaced the oil pump and the sreen on her 1.8L Not an easy task. This isn't my first rodeo. I've worked on many engines.

AndreasPassat: You are thinking like I have been. But, I was thinking it would be very difficult to find the source of the problem in the wiring (Connector, or connections etc. along the way to the ECU. I'll get it up on a lift nd have a good look. My oil pressure is really good. 3 bar.

Thanks for the replies guys!
 

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I was thinking it would be very difficult to find the source of the problem in the wiring (Connector, or connections etc. along the way to the ECU. I'll get it up on a lift nd have a good look. My oil pressure is really good. 3 bar.
Might there be a small chance a piece of dirt is stuck in the sensor orifice? I know the chances are probably nil, but gotta ask. I can't remember the route the oil sensor wire takes, but once it's up inside with the rest of the harness, the chances are slim anything is wrong with it up that far. I'm thinking only in the area where the run of wire is by itself outside the wiring harness / exposed portion would be compromised.

Do you have any other symptoms on the instrument cluster that would indicate a failing ABS module. It's my understanding that a failed ABS module certainly causes weirdness on the dash but NOT an audible signal for low oil pressure. I might be wrong on that though. I've never experienced ABS failure on a B5.5, only on my B5 V6. And that never was audible.
 

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Discussion Starter #10
AndreasPassat,
I have purchased another oil pressure switch which I hope to get to install this week.

I'll let everyone know whether that resolves the issue. If it doesn't, I will be looking to replace the wire and connector from where the wire protrudes from the wire shielding harness cover) down to the switch. I don't drive this car daily, so other needs are more pressing today. Thanks
 

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Discussion Starter #11
Very unusual to experience spurious oil pressure warnings on the B5, with the exception of those caused by a bad ABS module. Any brake warnings? OTOH, it's quite common to experience low oil pressure after the engine is fully warmed. If you're determined to disable the warning, try disconnecting the wire to the sensor (it's a simple switch). You may need to short the wires together; I'm not sure if the switch is normally open or closed.
I don't really wat to disable the factory oil pressure system and I will only do that if I can't easily resolve this issue myself.
 

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Discussion Starter #12
Update

I grounded the wire harness at the oil pressure switch location. The oil pressure warning alert did not activate on a test drive, This proved 2 things to me. 1) The switch operates by closing the circuit. 2) The wire harness is not damaged or faulty.

I then installed a 2nd new oil pressure switch and the oil pressure alert did not activate on a 10 mile test drive. I did all I could think of to perturb the oil pressure monitor system. It may be fixed.

Crossed fingers
 

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Update

I grounded the wire harness at the oil pressure switch location. The oil pressure warning alert did not activate on a test drive, This proved 2 things to me. 1) The switch operates by closing the circuit. 2) The wire harness is not damaged or faulty.

I then installed a 2nd new oil pressure switch and the oil pressure alert did not activate on a 10 mile test drive. I did all I could think of to perturb the oil pressure monitor system. It may be fixed.

Crossed fingers
On my '05 Nissan Titan, I had an issue with my pressure sensors in the braking system. after lots of head-scratching and replacing parts, we ran a ground wire directly to the battery and boom, all the issues stopped.

my guess is you probably found your problem. fingers crossed for you.
 

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Update

I grounded the wire harness at the oil pressure switch location. The oil pressure warning alert did not activate on a test drive, This proved 2 things to me. 1) The switch operates by closing the circuit. 2) The wire harness is not damaged or faulty.

I then installed a 2nd new oil pressure switch and the oil pressure alert did not activate on a 10 mile test drive. I did all I could think of to perturb the oil pressure monitor system. It may be fixed.

Crossed fingers
If that's the case, you'll probably want to check the ground points on the firewall right behind the coolant reservoir and the grounding wire from the passengers side motor mount to the body frame tube.

Glad to hear its likely resolved. Nothing like a car that functions like it's supposed to. ;)
 

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Discussion Starter #15 (Edited)
I think the first replacement switch I installed when this all started was faulty from the begining. That sent me off on the path of thinking it had to be something other than the oil pressure switch. Not! Don't you hate it when a brand new part is bad. It leaves you questioning your diagnosis and scratching your head and chasing your tail.?
 

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I pretty much always assume a replacement part could be defective. I've been right far too often.
Sad, but oh so true!


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