VW / Audi: 1.8T engine oil pressure checking 

jdmluisp Thanks for watching & taking the time to comment!

Yes, that's the first thing to check after switches have been ruled out.

Year of car? 1.8T I assume? mk4 oil pressure specs: Engine oil temperature at least 80 °C / 176 °F (radiator fan must start up once) 2000 RPM: 2.7 to 4.5 bar Above 2000 RPM: maximum 7.0 bar

@@EXOVCDS Hi Thomas, yes 1.8T, 2003, AWM. Sorry, I left out the subject line, or that which I've now added.

stuzman52 It will probably make it for some time longer, but eventually a decision will have to be made by the owner. My cameras are ready when she is.

Post a video on you channel so that I can see & hear.

Yes, could be.

No... some oil will come out when you remove the switch, this is normal. Place a rag under the switch to catch the oil.

Here's some good info: www.audizine.com/forum/showthread.php/610203-1-8t-Oil-Pressure-Survival-Guide-and-troubleshooting-DIY

The only way to be sure is to drop the pan again... usually, a restricted pickup will cause consistent / repeatable issues / oil starvation. Depending on how long you drove with low oil... you could have worn out one or more bearings. With the pan off, look for fresh debris and or even pull one or more connecting rod caps & crank bearing caps to check the condition of the bearings. If money is tight and pressure loss is due to worn bearings, thicker oil can cure oil buzzer & light issues (at least for a short while... until the actual repair is done).

Most likely oil pickup screen... changing the pressure sensor is easy & cheap, so you can try that first,

No. Check your oil level and check for oil leaks. If the switch was over tightened, it might have fallen apart and caused engine oil to spill out.

There is only so much that can be done / checked... it doesn't make sense to anyone why there would be low pressure, if all the required components are OK. It should not be electrical / software if a mechanical pressure gauge was used to verify lack of pressure. Thinning of the oil (due to fuel contamination) was my last guess. Most mechanics (like myself) can not take the time to diagnose a difficult problem full time... it would cost the customer too much. The quickest thing would be to change the engine... but that would not tell anyone what the actual problem was and at the worst case, the problem could still be there. If the engine did not have any low oil pressure issues after the initial rebuild... then something is obviously causing a problem over time (wear of internal components or oil contamination).

For a given rpm... different values (when cold or warm). Pressure will decrease as engine gets warm (oil gets thinner). I saw difference in pressure at the same rpm & temperature.

toyo toe Yes, probably one of those items... no check engine light, just the low oil pressure warning intermittently.

If the engine stopped... might have oil pressure problems. Was the engine noisy?

yes it had so kind of noise

Engine damage probably, sorry.

It is normal to see < min at hot idle... as long as it goes to OK above idle, you have nothing to worry about.

Thanks so much Thomas!

Not sure... could be in the bottom end of the engine or in the upper end of the engine.

Ok I'm going to check those first thanks

Also check your oil for fuel contamination... which can affect pressure.

I'm still at work.. will reply again later tonight once I am at home.

What year? Here in Canada, we do not have 1.6L TDI engines... I might have service information that I can look for, to see if I can find anything that you can check. What is the engine production code? Something like ALH, BEW... should be printed on a sticker on the valve cover or the upper timing belt cover.

Wht u mean ALH,BEW ? 2015 years .CAYAT engine

CAYAT... thank you. Now I can look for information.

I could not find information for CAYAT engine, but I found information for CAYA engine. I don't know if that is the same one. Is the oil pump driven by a belt? Is the tension correct? Are you using the correct VW oil? What type of oil filter are you using? Remove the oil filter bracket and check if there are any valve inside of it... clean the assembly. I don't know what else it could be... you have already replaced the major components.

+Rick Worthington Doesn't have to be tapered (the stock switch isn't)... as long as the "thread diameter & thread pitch" is the same / of the correct size, the fitting will work. If not tapered, then the fitting needs to sit tight with a sealing washer (like the pressure switch)... if tapered, it just needs to be snug. I can't remember where I bought this gauge... it came with a variety of adapters.

Straulf Kimburg VW /Audi pretty much have standard oil pressure specs across the board: fkh161.ca/VW/APU/APU.pdf

+Rumen Hristov I don't recall there being a test port at the head... noisy lifters is a good sign of low pressure. The chain tensioner has its own filter screen (could be plugged restricted), but the tensioners will get noisy as they fail with age (or a cheap aftermarket tensioner will make noise).

Thanks very much Thom. Perfect answer as always!

My passat 1.8T had 230 000kms on it and the motor was running so quiet and so smooth you didn't know it was running. So I am amazed when I see all these 1.8T's with low oil pressures and noises and what not. In my experience this engine is an engineering marvel and I can almost not believe that anything like that can happen to it, let alone happen often.

Obd will only show if pressure is good or bad... same as the warning light & buzzer, so you don't need to use obd. If problem happened after service... it could be wrong oil.

@@EXOVCDS Thank you so much for . Action plan first change the oil if it fails then maybe change sensor. Technican said that used 5w30 as always used. Engine is 210k km should i switch 5w40

5w40 can help. If problem happens even when engine oil is cold (thick), then it is probably the sensor.

There is another issue now :) Coolant error also occured. Oil pressure and coolant error now both exist :) I am suspecious abaout head gasget this time. There is also corruption and heat damage seen Coolant rezervoir bottle. Many thank Thomas for your support

If the warning only happens when the engine is hot... chances are that it is a true warning. Oil gets thin when hot, thin oil does nor produce pressure as well as thicker oil. Filters should have bypass valves within them... when the oil is thick, it bypasses the filter. As the oil warms, the bypass closes and the the oil gets filtered. A filter could affect the pressure if not enough flows through the filter... but I would think that the bypass would open again if the paper is too restrictive. Checking the pickup screen is always one of the main things to check. With the pan off, main & connecting rod bearing wear should be checked. Edgemotors has a great de-sludging video.

@@EXOVCDS It is great. As you are. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-zFOqW0x7oiI.html

jennavica luis what color is your coolant?

It is probably part of the fuel filter. If your fuel filter has 3 lines that are attached to it... one of them (the blue one) is attached to the pressure regulator.

It was in the Filter, did not check it last time i looked. Thanks a lot 👍🙂

Thank you for the update.

+Cant truss it Depending on the year: www.germanautoparts.com/Volkswagen/Passat/EngineElectrical/150/6 or www.germanautoparts.com/Volkswagen/Passat/EngineElectrical/150/5

+Cant truss it I would remove the oil pan and check the pickup screen for the oil pump... could be plugged up.

yeah... that's the place where you will want to tap-in too. There might be a "plug" at the top of the flange that can be removed and tapped in too. I'll have a look at the next Passau I have in my hands to confirm.

Thanks alot!!!!

+Andy Wardle Yes, as the engine wears, oil pressure decreases... 1.2 to 1.6 bar is when the oil pressure switch is supposed to close, if it does not, then the oil warning light will come on. As per 1.8T AEB service manual: Oil pressure at 2,000 RPM: minimum 1.3 bar. Oil pressure at 3,500 RPM: minimum 3.5 to 4.5 bar.

+Thomas EXOVCDS Thanks so much for your answer. I have been struggling to find a definitive answer to this issue. All the forums telling me my oil pressure is too low, while at the same time, apart from the oil light and buzzer, the car runs perfectly, with no knocks or rattles at all. I will be fitting the brown oil pressure switch, which closes at 0.55 to 0.85 bar. Thanks again. More power to ya! :)

skurtov Sorry about the late reply... I will measure it today and will get back to you. Most oil pressure testers will / should come with a bunch of adapters.

Thomas EXOVCDS all good. Thanks for getting back to me. It's actually m10x1. Luckily the Harbor Freight kit i got comes with one

skurtov Yeah... that sounds right. I'm just finishing lunch and then was gonna check. Good to hear your kit has one!

Turbo gets fed right from the filter housing... meaning there should be enough oil supply as long as things are OK. The feed should always be replaced... guess you could check the flow out of the feed line at the turbo end.

+Thomas EXOVCDS The exhaust side nuts were loose... But I also discovered a bent impeller fin! Just one, all others were fine. Weird, nothing found in the intercooler, PSI is aobut 16 at hot idle and 65 at 3k hot. My thermostat was bad for quite a while, all I can think of is excess moister freezing in the tip or the entry of the turbo.

Hi Frank... all is good, but it's slow at the shop right now. The 1.8t is smaller and has more room to work around the engine (kind of)... the V6 has more reliable power & less need for servicing (overall in my opinion), but it's heavier and not as good on gas. I would probably still go with the V6 & std Trans (the V6 also bends valves... haven't had the pleasure yet though to pull one apart). We've got several customers with 1.8t Passats /Audi A4's that haven't got any engine problems at 200k+ km. I think either will serve you well as long as you find a well maintained specimen.

***** Thanks for the reply Thomas..Reason I asked is cause from time to time when I lurk on craigslist I find either them very cheap..of course with issues with turbo or t belt..(engine) But since you mention not good on gas,I will get away from it.I already have a truck that take care of that lol..reason i rarely drive the vr now..

guayaco3299 Forgot to mention the possible water intrusion issue that can flood the floors... it's mainly age though that plays a role overall (as with any old car). There are two types of Passat owners, those that love it and those that hate it!

***** LOL...Actually Thats the same of all vw's.. I always said it vw's are a love/hate relationship....

Once the connector is removed, you need a 15/16" or 24mm deep socket to remove the oil pressure switch. If you can not get the electrical connector off, follow the tip at the end of this video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-gf0nD2SeQzA.htmlm6s

Thomas EXOVCDS thank you for getting back to me!! I'll give this a shot...I'm hoping it's just the oil pressure sending unit otherwise I've got much bigger issues.

Thomas EXOVCDS hi i have oil pressure issue in a 2004 1.8t passat 4 motion awm head. engine blown and then we got an aug engine head code after replaced have this issue problem can be due diferent head

chekizz p Are you asking me or telling me?

Thomas EXOVCDS im asking if that could be the reason for the oil press failure in the engine that we installed its the same engine block but diferent head original was awm code and now has aug code i hope u can understand me thanks for response great vid btw

Pull the oil pan and check the pickup screen... clean & or replace the pump while the pan is off.

Sorry, I meant clean the screen, not the pump. If there's lots of sludge in the oil pan, then there can be a lot in the cylinder head. A complete engine flush / cleaning might be needed... but that can cause stuff to get places where it should not be.

Thomas EXOVCDS ok thanks looks like I'll have to stop driving it until I fix it

Thomas EXOVCDS what about the likeliness of it being the sensor?

BlueXorcist19 Could be, but not most of the times. Easy enough to eliminate, remove and install a new sensor.

Oil pressure switches usually don't fail / produce a "wrong" signal... but they will leak when they get old. What I mean is that if you are having oil pressure warning light issues... it's most likely due to oil starvation rather than a switch that is faulty. However, replacing the switch to see if things change, is a cheap first step. Oil pump failure / life can vary greatly... lack of oil changes & using the wrong oil are the biggest causes of premature failure.

@@EXOVCDSmy oilpressure light comes on when im in the highway doing 110/120 km an hour.. The oil wasent changed for a long a good period when i got it, and it was Very dirty! After the change the oil pressure light comes on... I can drive it in the city no problem, but highway is a different story! Can it be old dirt clogging up or maybe the pump?

@@kimnielsen4343 Most common issue is plugged up pickup screen for the oil pump in the oil pan... on 1.8t engines.

@@EXOVCDS ohh.. time to drop the damn oilpan then 🤔 what do you Think About flushing? Bad Idea? Any ideas on How to get it off easier? No way around dropping the subframe? 🤔

@@kimnielsen4343 have to lower the subframe (Passat / Audi A4). Flushes can work and make things worse. Oil pick-up screen is my first guess... a few months ago someone had a similar issue and the screen was fine. New pump didn't solve things... could be something else. Try a new switch and then thicker oil. If it is better with thicker oil, then there might be bearing / clearance issues.

Check for sludge in the oil pick-up screen.

i got the oil pump replaced and the cam camchain tensioner. what else could it be ?

Kimble Trainer Oil gallery restriction? Cheap tensioner? What's the actual oil pressure? Does the oil pressure warning light & buzzer come on once warm? Something might not be sealing well.. crank or piston bearings, cam caps worn? What oil? Try using something a little thicker as a test.

oil pressure light doesnt come on anymore.

Kimble Trainer Oil pressure sensor is mounted to the engine "below" the cylinder head.... meaning that you can have low pressure at the top and not know it. I am not aware of a way to check oil pressure at the top of the head... unless some kind of access hole is made somewhere. Have you tried some kind of chemical oil change flushes? Here's a good video on cleaning a 1.8T: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-zFOqW0x7oiI.html contact them to see if they know of where you could check pressure at the head.

Yes... the 2003 should have the pressure switch in the same location.

Thank you for the help

Year & engine?

Thomas EXOVCDS me personally I have an audi s3 2003 with 1.8t bam engine, mine is running good, but with this particular engine in video what we're the customers options?

For oil pressure... as basic as just a pump. Once you have noise.... crank & connecting rod bearings & a pump. Long block (new). Used engine. Complete overhaul of old engine. All depends on the customer... which way they want to go.

Choices.. lol! i changed the o-ring for the oil cooler on mine last weekend as precautionary being a 2003 car (sorry - heat exchanger :) ) much prefer doing preventative maintenance on my cars.. was thinking of dropping the sump, clean and then refit with new pickup pipe. the car has 119k miles would it be worth changing the oil pump too?

LOL... oil cooler seal would have just been a matter of time before it was going to leak. At every oil change, check if the nut is still tight. The oil pump, drive gear & chain (I think it has that type of setup) would be good preventative maintenance, yes.

VCDS or scanner will only show "pressure ok, pressure not ok"... it will not show "what the pressure is". When the light blinks & the buzzer beeps, we already know that pressure is NOT ok. You need to know what the actual pressure is, to determine what your next course of action will be.

stupid fakking vag i am so sick of it. i convert to Benz :) i have the c5 1.8t myself and nothing but fakking troubles Thanks! Regards: Johan

Over 90 percent of vehicles on the road "do not" have an oil pressure "gauge" in the dash... so it's not just VAG.

not just vag you are correct my good sir but they should know better when they designs these cars in a old drunken german pub.. ;) HAha

ROFLMLFGAOAU!! ;) HAha

Oil light comes on at idle or at 2000rpm?

around 2k. i took oilpan out and i was going to clean the pickup tube but it was not even dirty at all...

Make sure you don't have any wiring issues and that the correct pressure sensor is used.

Thomas EXOVCDS I have the same issues change the wiring as well and the oil pump and the pressure switch twice but no engine noise what do you think is the issue?

Domperoid Or used... we will have to wait and see.

Yes... on the 1.8T it is located above the oil cooler.

Thanks, i need to check the pressure im getting the stop the motor now message even though i have plenty of oil.

The oil pickup screen in the oil pan could be plugged up / restricted.

gonna flush the engine with some liqui moly proline and see if it cleans it out if not i guess i am dropping the pan

what kind of pressure readings should I be seeing? I be seen a ton of topics about removing the screen in the pickup tube .

I feel your pain... I have the same issue. Move what you can to get more room. As snug as you can get it (for a more accurate and less messy reading). Odds are... because it's a 1.8T, the oil strainer is plugged / restricted. Oil pressure switches don't usually go bad. When they do, it's more of an external leak issue, as opposed to causing a circuit fault.

@@EXOVCDS thanks for the reply! I managed to get it as tight as I could without stripping the threads. Oil very, very slowly oozes out but not enough to cause problems with the readings. Do you think it's a good idea to wrap teflon tape around the oil pressure sensor?

@@Farseer1995 Teflon tape should not be needed.

I don't know... since I don't know what the problem is.

Sorry its about the 1.8tfsi Audi engine

I still don't know what the problem is.

my gf Audi developed a misfire Cut long story short Valve seals needed reseating done the timing chain And now the oil pressure warning light has come up red

Changed the oil sensors Changed oil pump Changed pcv Bought good quality 5-40 oil It does not come on straight away only once engine is warm

Nick Forsyth I have several deaf people who watch my videos... I think you have a problem if you can't follow what is happening in the video.

Nick Forsyth it's not real hard pal... you pull up the coolant reservoir, use a 24mm or 1 inch socket or wrench to get the sensor loose, thread the oil pressure test tool in by hand and tighten it with an appropriate wrench. wait for the car to get warm and see if the pressure is at at least 19 psi at 2k rpm and 50-65 at 3.5k rpm