2000 A4 Avant 1.8 T Sport Oil Pressure Sensor Failure

Anyone know anything about this?

We had a sensor failure (or blockage?) back in May or something at which point the sensor was replaced, and it looks like it's happened again. Got the critical warning about oil pressure, but oil pressure IS good (or else the engine would have died a thousand deaths by now...) Only happened after driving 20 miles or so at 80mph.

It's a cheap part to replace, but is this a known issue or have I been singled out by some sort of evil conspiracy, or perhaps even ALIENS?!?!?!

Reply to
Marcus Redd
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1.8T? Could be the dreaded "sludging/oil coking" these motors are known to experience. Might want to have the pan dropped and check pump inlet screen and pickup tube for clogging.
Reply to
Keep on Plonkin'

You *are* wearing your tin-foil hat while driving, right?

IMHO, if nothing else, sometimes things happen. I've replaced five thermostats on my H1 Hummer, but no one says its a known issue! However, once you get to five, then you can say (as I do) "It's a know issue!"

Reply to
PeterD

Known for decades and not just in A4s, not just in 1.8s, not just in Audis. Why the Bavarians insist on specifying and using these pieces of crap for such an important function I can't imagine. One good thing about them is what you mentioned: they're cheap. Two other good things about them are:

1) You can buy 'em almost anywhere - I get mine at AutoZone. 2) They're really easy to replace on the BMW M30 3.5 head ...

-- C.R. Krieger (Been there; done that - too many times)

Reply to
C.R. Krieger

That's cheered me up quite a bit - thanks!

Reply to
Marcus Redd

Thanks, I've heard of that, but, as I said, the engine is fine despite running it afterwards (after having the AA guy checking that oil is still moving around) so I really don't think this is the issue - it had a complete oil change just a few months back anyway, with the correct fancy silicon or whatever oil.

Reply to
Marcus Redd

Tin??? You mean this baking-paper-bonnet I'm wearing is insufficient protection? Where can I get this "tin-foil" as you call it?

Hehehe, well, it's becoming an issue known to me, that much is true. Maybe I'll just buy a six-pack of sensors and change them whenever I'm bored.

;o)

Reply to
Marcus Redd

Oops, terminology mismatch! Yes, the baking-paper-bonnet is fine, sufficient.

I'm not sure I'd recommend that, but if you can get them from a couple of different makers you may find one make is better than another...

Reply to
PeterD

So I assume you've had the oil pressure verified with a mechanical gauge when cold and hot? You may not want to rely upon the fact that the engine has not yet experienced an oil-starvation failure just yet, if your oil pickup is clogged it will still run with low pressure for some period of time, with accelerated wear due to low pressure. These engines have such a small sump due to their marginal design that they now require a strict oil change interval of 5000 miles with a larger filter (to get the oil capacity up to more than 4 quarts) and a VW/Audi-approved synthetic oil (in the US the most common of these oils are Mobil1 0w40 and Castrol Syntec and Valvoline Synpower 5w40).

Unless you say for certain that your motor has adhered to these requirements since new you have a possibility of having an oil starvation problem due to oil coking. And unless you can prove to Audi you've adhered to their oil/filter/change schedule, you'll be SOL on any warranty coverage.

Reply to
Keep on Plonkin'

So I assume you've had the oil pressure verified with a mechanical gauge when cold and hot? You may not want to rely upon the fact that the engine has not yet experienced an oil-starvation failure just yet, if your oil pickup is clogged it will still run with low pressure for some period of time, with accelerated wear due to low pressure. These engines have such a small sump due to their marginal design that they now require a strict oil change interval of 5000 miles with a larger filter (to get the oil capacity up to more than 4 quarts) and a VW/Audi-approved synthetic oil (in the US the most common of these oils are Mobil1 0w40 and Castrol Syntec and Valvoline Synpower 5w40).

Unless you say for certain that your motor has adhered to these requirements since new you have a possibility of having an oil starvation problem due to oil coking. And unless you can prove to Audi you've adhered to their oil/filter/change schedule, you'll be SOL on any warranty coverage.

Reply to
Keep on Plonkin'

The car has done over 4,000 miles (it's now at just over 50k miles) since the first oil-pressure warning incident (when the sensor was replaced) - are you saying the engine could have survived that long whilst oil-starved? Also, with the new sensor, there was no warning, so do I assume that the first sensor was NOT faulty and that the new one IS? ;o)

It's been serviced by Audi whenever required by them, but if you look at my subject line, you'll see it's out of warrantee now anyway...

And are you seriously saying it needs a complete oil-change every 5,000 miles???

Reply to
Marcus Redd

When these engines "sludge", they do not lose all oil flow-- it is reduced to some marginal level for some period of time, which causes insufficient lubrication and increased wear. The engine runs, but the bearings experience increased wear (VW checks the cam bearings for wear for this problem, and replaces the entire engine if wear is out of spec). Given the known problems with this engine, it is unwise to keep driving them for any length of time when you get a low pressure warning without pulling the pan and checking for "turbo turds" (hard coked bits of oil) in the oil screen and pickup tube. Given your mileage (and possibly your service history) your motor is a prime candidate for this problem.

If you get an oil-starvation failure you may need a new engine. Because of this problem, VW/Audi extended the drivetrain warranty against sluding, provided the owner has proof of proper oil changes. Even today, some VW/Audi dealers continue to use the wrong filter and oil in these engines.

Yes, that is what is required, along with a larger filter (increasing oil capacity by about 0.5 quarts) and the use of synthetic oil meeting VW/Audi

502 specs. This was outlined in TSB in 2004--check with your dealer's service department about this. I know the relevant VW TSBs are 17-04-01 and 17-04-02. (engine oil warning) and engine oil and filter specs.

Just enter the following into Google, you'll find plenty of info:

+VW +Audi +1.8T +sludging +larger +synthetic

A few results:

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VW Passat and Audi A4 use essentially the same engine mounted in the same way, so 1.8T info for either applies to both.

Reply to
Keep on Plonkin'

Yes. It's not out of warranty for the Sludge issue. (Warranty was extended for this) See my story at

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Of special note is that the Audi dealer claimed a faulty sensor for mine (they screwed around with me replacing the LEVEL sensor even though it was the pressure warning that lit).

The pressure warning will light when the pressure gets bellow 20psi at speed. That's enough pressure for the car to run for a long time. Changing the oil may restore some oil pressure by removing some large particles that are temporarily blocking the oil pump suction screen, giving you some reprieve.

GET THE PRESSURE CHECKED

First, you yourself can simply look in your oil filler cap and see how things look.

Hope it's not sludge

--Art

Reply to
Art M

Reply to
Marcus Redd

Art - thanks for this info.

Is there any official Audi site where this extended warranty is mentioned?

I've looked at the letter you received - is it possible this only applies in the US? I'm in the UK.

Reply to
Marcus Redd

...

I never received the warranty letter. It's possible that the previous owner did. That link on my site is to someone elses site.

It's possible that it only applies in the US. Here Audi (of America) paid for oil changes at 10000 mile intervals, but they allowed and used mineral oil at those long intervals instead of synthetic which I'm told was a bad idea in a turbo.

So, have you verified that you do have an oil pressure / sludge problem?

I'm always interested in hearing about the oil change history that led to that. If you want to tell me more you can send me a message at arthurruhtra at netscape dot net.

It's an understatement to say I'm not a big fan of AoA. It's bad enough they didn't cover my sludge problem under warranty at 36k miles, but they negated the warranty and refused to cover anything as unrelated as a broken radio and refused to do the 40k service work at no charge.

--Art

Reply to
Art M

Ok, just got the car back from Audi as it finally developed bad noises from the top-end on Christmas Eve - nice...

They confirmed it WAS a sludge issue, dropped the sub-frame, removed the sump and cleaned it all out. It now has fully-synthetic oil in it.

The engine appears to be fine - the contact guy at Audi commented on what a lovely quiet engine it is. It's pulling like a freight-train again and sounds just as inaubible as it did before the incident.

Regarding the warranty being extended - that appears only to be true for Audi in the US. I emailed Audi UK and got this response:

Total bill was 370UKP. Ironically, I was intending taking it to Audi in the days immediately following Christmas to get the oil pressure checked, as I was really not happy about it continuing to beep after having a second sensor replaced. Just as a quick recap, we had the pressure-sensor replaced back when we bought the car in April '06, as well as a full oil-change and new filter, which made the problem go away until November. I find it hard to believe that the car has been suffering from low oil-pressure for all of that period and yet the engine still sounds as quiet as it does.

Anyway, thanks for your interest and taking the time to reply.

They negated your warranty??? How could they do that?

Reply to
Marcus Redd

snip

The dealer said Audi was calling it a "neglected vehicle" because the previous owner went 12,400 miles before the second oil change (with mineral oil and the small oil filter the dealers were using back then). From cases I've heard of around here VW is much more accommodating than Audi on the sludge issue.

I bought the car directly from a friend. He asked the service manager to make sure the warranty would still apply to me and to find out if there were any problems with the car. They had to know it had a sludge problem. Anyone who knew about the sludge issue and who looked in my oil filler cap could tell. I got free service work at first, but once they diagnosed and admitted it had sludge I was denied coverage on anything. The only work they covered since then was replacing the recalled fuel pump.

--Art

...if they didn't clean the engine head and valve cover you'll probably have to do some frequent oil changes now.

Reply to
Art M

Gee, sometimes you do get good advice on Usenet.

Did they check the cam bearings for excessive wear? That is where the wear shows and is what VW/Audi uses to determine to replace the entire engine.

Reply to
No Spam Please

Gee, sometimes you do get good advice on Usenet.

Did they check the cam bearings for excessive wear? That is where the wear shows and is what VW/Audi uses to determine to replace the entire engine.

Reply to
No Spam Please

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