Oil Pressure Beeping

[h.ubk]

Hi All,

I started driving today in my 1997 Jetta Tdi and the oil pressure switch started flashing and beeping. I drove the car about 1/4 block back and parked it.

I just purchased an oil pressure test kit at Harbor Freight. What values should I be seeing as normal?

I am planning to order part #068-919-081-A-VAG. I believe this is for the oil pressure switch on the cylinder head. Is there a second switch or is this the only one? I would rather err on the side of caution and put a new switch in there as long as I am going to the trouble.

Thanks,

h.ubk

 

[Mongler98]

basically 10PSI per 1,000 RPMS
The 1Z / AHU run in healthy condition at about 30 to 40 PSI to even 45PSI when cold higher the colder it gets. about 15PSI at idle when nice and hot at proper operating temps with good oil. You will see about 8 psi when warmed up at idle on a heavily worn engine or one with a worn out turbo or valve tappet journals. You will know if the turbo is worn down if at boost you gain PSI at the same RPMS under load, if it falls at higher RPMS then it could also be the head. as long as you have about 30PSI when running at 2500 to 3500 RPMS your fine. anything less and you have an issue i would fix before driving it other than to test.

 

[h.ubk]

Ok, thank you. I'm ordering the pressure switch tonight.

The turbo should not be worn out as it is a new OEM unit with less than 10K miles on it. The head and valves are also new OEM and replaced in the last 15K miles.

h.ubk

 

[Mongler98]

eh, i've seen rebuilds go for 25K and crap out due to inferior parts. there is a bad set of valve lifters that ID parts used to sell and they ended up in a fair bit of remanufactured heads sold by various places. IMO remand parts are garbage unless rebuild by a pro we trust or by yourself with proper information. Low oil pressure will KILL your turbo and cam and really, any parts downstream of the debris sent out by it. Not trying to scare you. Good news is that the oil pressure switch does tend to fail so it could be that simple. I have also seen engines that get starved for a few minutes of running with no ill effects but have first hand experience with the other side of things too. The oil pump on these engines can also wear out.
My preference is with AUBER gauges as i can wire in a shutoff or alarm with the built in relay. Defuel, nitrous hit, Water meth hit, you name it, you can program them to do whatever you want as well as read out of whatever you put on them.

 

[h.ubk]

Regarding the head, it is a NOS OEM part that has been sitting since the 1990's, so I would hope the quality would be good.

So, I pulled the sensor out of the head and ran the oil pressure test for about 3-4 minutes. The oil popped up on the gauge at around 60psi and dropped as the engine was warming up.

At about 4 minutes, I started increasing RPMs to 2000 and the oil beeping sound came back. The sensor is disconnected. Is that normal? Or is there another sensor maybe in the block? It would appear the oil pump is working properly.

Thanks,

h.ubk

 

[Vince Waldon]

Yes, the system is RPM sensitive and so will be noticing the missing sensor after 2000 RPM.

Various versions of the system have one sensor, many have two. Tracking down the actual service manual pages is probably the best way to know for your specific model year.

That said, if there are two sensors one will be on the oil filter mount and the other up on the head. One is normally open and the other normally closed, and they have two different operating pressures. Not uncommon to put the wrong ones in the wrong places, or for a parts guy to sell the wrong one.

http://vincewaldon.com/index.php?option=com_content&task=view&id=40&Itemid=28 has a write-up on the nuances of the dual-sensor system.

 

[h.ubk]

So, it looks like I have a oil pressure sensor at both the head and the oil filter housing. Does it matter which one I use for the test? I was testing the oil pressure sensor from the head, but it looks like the sensor that is beeping is coming from the oil filter housing.

h.ubk

 

[h.ubk]

Ok, it looks like the link is referencing to test from the oil filter housing. The switch I ordered is for the oil filter housing, so I will wait until I get it and install in there and then test the pressure separately with the gauge.

h.ubk

 

[Vince Waldon]

Yup, the oil pressure is very low by the time it gets to the head, so the test site is on the oil filter mount.

 

[h.ubk]

So, I received the new sensor today and put it into the oil filter housing. Once again, I get oil pressure warning buzzer.

I went for a test drive to get the temperature up to normal and connected my Harbor Freight oil pressure gauge, this time to the oil filter housing not the head.

At idle, it is about 21psi and at 2000RPM, it is running at about 60psi.

Does this mean I am ok?

I am almost ready to swap this engine and get rid of all of these VW related problems. I bought a Geo Tracker earlier this year and am planning to buy the conversion kit from ACME Adapters. I just need to drive it from California to Idaho to get to the Tracker and then pull the engine.

I am thinking about just putting in a mechanical gauge, which wouldn't be a bad idea for the swap anyway.

h.ubk

 

[Vince Waldon]

Yup your oil pressure is fine, so assuming your new sensor is the correct polarity and pressure for the filter housing it sounds like you probably have a wiring (between the sensor and the cluster) or cluster circuitry issue. These beasts are getting on in years and so the odd electrical-related problem is not uncommon.

Gauges are always *my* personal preference to warning lights... but that's just me.

 

[h.ubk]

Ok, I'll add an oil pressure gauge then. I was planning to do that after the swap anyways.

How do I make the beeping go away in the cluster?

h.ubk

 

[h.ubk]

I took the cluster this morning to a repair guy and he pulled out the speaker for me. It was actually easier than I thought. Now, I have blinking oil pressure light in the cluster and no noise so I can drive it again.

h.ubk

 

[Mongler98]

You have got to be kidding me.
Please. God let this be a joke!

 

[h.ubk]

Why?

h.ubk

 

[Mongler98]

Just fix the issue lol. Even if you know everything is good, like I did with my auber gauges. A $0.45 resistor would do the job and take 5 seconds to install into the harness for the oil pressure transducer and to a ground somewhere, anywhere.

 

[h.ubk]

My wiring harness is totally messed up. The previous owner tried to fix the harness and the dealer wouldn't touch it. He then bought another harness and installed it. I spent a lot of my own time as well as brought it to my German mechanic who then was being advised by his VW expert friend. The entire electrical system in my car is messed up and we ended up with the stupid wiring diagrams from VW in the Bentley are incomplete.

I am swapping the engine into the Geo Tracker in April. I'm not driving the car every day. I am putting in VDO gauges which is what the car should have had in the first place. There's a reason why I can drive a vintage Mercedes diesel as a daily driver and the VW diesel is a garage queen always waiting for parts from some far-off place and stupid tools that nobody outside of this special world has heard of.

These VW systems are complete junk. I can say that from driving Mercedes diesels for about 12 years. I am so sick of people on these forums rolling their eyes like just fix it and when you bring it to the experts they say it isn't worth fixing and they can't fix it without putting in more labor than the car is worth.

h.ubk

 

[Mongler98]

Experts you bring it to, pay 130 an hour
everyone here, we will do it for a beer if your close enough. pick your poison.

 

[compu_85]

IMHO the VW dual switch system is way better than the no alarm (!) system Mercedes used.

The diagrams in the Bently are quite complete from my experience. If you're looking to do a swap, I'd suggest you get familiar with them and how they're laid out. Also check out a2resource.

-J

 

[h.ubk]

Oh, I'm so sick of this. Everyone says this until you post a real questions. I have in my history here detailed questions asking about missing parts of the wiring diagram on the Bentley and nobody, anywhere has any answer about it. The previous owner also was on this forum and put a substantial amount of work into fixing the harness. He did not want to get rid of the car.

If your oil pressure is low because of no oil, then shame on you for not watching it. If you blow a line or knock out your oil pan while driving, your engine is already toast. And probably the same if your oil pump fails while driving.

The only thing the oil pressure alarm is good for is to alert that your oil pressure is low for something on the engine that is serviceable. But, even then the majority of people say that 90% of the time it beeps because the sensor is bad. So, if you are out driving and your oil pressure buzzer comes on, you have no way of knowing if your pressure is actually low and if it is a condition that will damage the engine. With a gauge, you can actually watch it over time (I do this on my Mercedes and observe the pressure under different situations) and determine if something is degrading. The only problem I have seen on the Mercedes is the mechanical gauges can leak oil, but that is very rare. They almost always work mechanically like a Swiss watch with no power even after 40 years without complaining or needing replacement parts.

h.ubk

 

[Mongler98]

OH i agree 100% that the oil light and coolant light/ temp gauge is 100% useless to save your engine from damage. only actual gauges that do something are good. any regular gauge is ok, but again, almost worthless when the time comes. For Instance. Auber gauges have a relay within them you can make do whatever you want by using your own set or parameters.
I used these gauges with boost, and EGT's to do water fog injection to help control EGT's. I also had the break switch wired into the EGT's so that if they get too hot, i mean past 1560 it will defuel the engine. Same with the oil pressure. i had it connected to a timer that at ignition start up would count for 30 seconds. if i had less than 15PSI past that time it would shut off the car by opening the fuel solenoid. i ended up taking it off becaue of issues i had with my failing turbo's oil pressure making issues at idle. when it was hot.

Anything to be smart out this stuff past stock config or past the value of the car to be replaced. i would never do anything like that to a new car, why, $ and insurance. old cars worth a few grand with some performance or swap like stuff, yea absolutely.

 

[Mongler98]

I just thought that spending $$ on someone taking the speaker out of the cluster is so laughable when you could have spent less than a buck on a resistor on the wire.

 

[h.ubk]

He did it for free and I wasn't sure if I would end up disabling something else on the circuit that would cause a no-start condition. So, I was happy to take it for professional help. I don't have any confidence that anything done on the wiring harness would have helped.

h.ubk

 

[compu_85]

OH i agree 100% that the oil light and coolant light/ temp gauge is 100% useless to save your engine from damage. only actual gauges that do something are good. any regular gauge is ok, but again, almost worthless when the time comes.

If you're driving at speed and lose oil pressure you have at best a second or two before the turbo gets destroyed. When driving I don't look at the gauges 100% of the time - the VW dual pressure switch alarm is a great warning system since it warns you as early as possible about a loss of oil pressure.

You know the temperature gauge in the cluster is buffered, right? It will sit at 190*f from like 170*F to 220*F

-J

 

[h.ubk]

You know the temperature gauge in the cluster is buffered, right? It will sit at 190*f from like 170*F to 220*F

Yep, that's why I have a real gauge on mine. The Mercedes is pinpoint accurate even after almost 40 years.

h.ubk

 

[Master Sushi]

Whata the latest on this ,