Eric's wife's B6 A4: done

[savagerocco]

Think the speaker is in the cluster. Try output controls in instrument panel pretty sure you can command it on

[elaw]

Dude I owe you a beer! Or probably several at this point. :-)

Performed output tests, all was well except for one thing: no noise!

The cluster needed repair anyway as the LCD gets wonky in hot weather, I guess now there's an additional reason.

[savagerocco]

Np next time I'm out your way or vice versa

[elaw]

Just to close the loop on the lack-of-headlight-warning-beeper saga...

I pulled the cluster out of the car, pulled it apart, and the speaker was clearly toasted. A check with an ohmmeter confirmed that that speaker was going to be speaking no more. It had shuffled off this mortal voice coil, gone to the great stereo shop in the sky, etc. etc.

I did some googling and found some info where people suggested a certain part available from Digikey as a replacement (PUI Audio something or other). As luck would have it I actually had one of those parts lying around, installed it, and it works - but I would not recommend it.

First, it's not nearly as loud as the original speaker. And second, its power rating is considerably less than that of the original item and the original burned out... what does that say about the expected lifetime of the new part? It's not too promising.

So after a little more searching I found the "right" part for sale on ebay for 15 bucks and I ordered one.

[elaw]

And to close the loop a little more... the correct part arrived, got installed, and life is good! In addition to being less likely to burn out (see my previous post) it's a fair bit louder than the other thing I'd installed.

If anyone wants I could do a full writeup on the repair but it's pretty easy:
* Remove instrument cluster following instructions all over the internet
* Remove back cover of cluster: four Torx t-10 screws on the back and four plastic clips around the perimeter
* Locate the thing that looks like a speaker
* Grab soldering iron, remove old speaker, install new speaker
* Reinstall cluster
* Reset the clock

[elaw]

So here's a question for those of you with 1.8t engines... does your engine normally have positive pressure in the crankcase at hot idle?

If I loosen the oil cap with the engine running, it doesn't fly across the room but there's enough pressure to make it dance around and quickly fall off. My instinct tells me the engine has a lot of blowby, but this is the only 1.8t I've ever worked on so I'm not sure what's normal.

What prompted this is a fault code (plus CEL) that recently appeared for an intermittent low MAF reading. The intarwebs seem to think it's usually the MAF sensor or the wiring for its connector. I checked the connector wiring and it seems fine, but before I replace the sensor I'm just wondering if it might be reading low airflow because there are a lot of vapors coming from the crankcase and displacing air in the intake. I hooked up the VAGCOM and MAF at idle is about 2.6 to 2.8 something or others - grams/second? Anyhow the number was around 2.8 shortly after I started it (already close to fully warm) and after running ~10 minutes it was closer to 2.6.

I should add that I've checked almost all the check valves in the PCV system and replaced one (the one adjacent to the venturi vacuum pump thingy) along with the venturi vacuum pump itself. That was about 2 weeks ago, but the CEL just came on two days ago.

Edit: yeah, I know the "right answer" is to do a leakdown test! I actually have the tester, I just haven't been able to muster the time and energy to pull the $@#$# front of the car off so I can get access to the crank pulley. :frustrated:

[scubagli]

It's common for the pcv system to get clogged up with gunk and cause positive pressure. Replace with 034 parts or integrated engineering parts and call it a day.

Sent from my SAMSUNG-SM-G870A using Tapatalk

[elaw]

Sigh...

Well I've gone completely through the PCV system, replaced the PCV valve itself (the one under the intake manifold), and the MAF reading at idle is still about 2.8 g/s.

And it gets worse: I did a leakdown test. 24%/36%/27%/46%. I did the test twice and on the first test one weird thing happened. When I was testing #4 and increasing the pressure, the right-hand gauge seemed like it was going to end up at about 70 PSI (LH gauge reading 100 PSI). But I heard a single "click" and when I got to 100 on the left gauge, the right gauge read 96! I brought the pressure down to 0 and raised it again and got the same result (4% leakage). I'm wondering if a piston ring was stuck and suddenly snapped into place? I disconnected the tester, spun the engine a few revolutions on the starter, reran the test, and got 27% leakage on that cylinder.

Getting back to the maybe-a-stuck-ring thing, I'm wondering if a dose of seafoam in the crankcase might help. Has anyone ever experienced something like this and/or had a leakage problem helped by seafoam? At least with the two worst cylinders they're clearly leaking into the crankcase - you could actually see fumes coming out the oil filler opening (the engine was hot at the time).

Other than a possible miracle seafom fix, it looks like the engine is going to need rebuilding or replacing. My understanding is R&Ring the engine on these cars is pretty difficult - has anyone here done it? If we had to pay a shop to install a rebuilt or junkyard engine, it would cost about the same as replacing the car with a comparable one.

Hey... I don't suppose anyone here has a known-good MAF sensor for this car I could borrow? I'd be williing to pay a fair price to borrow one for a few days. It would be pretty easy to plug another sensor in and see if the MAF reading is the same and then I could have an idea whether the problem is the sensor itself, or blowby like I suspect it might be.

[rs4tech]

Tell me what your readings are for measuring value block 32 please

[elaw]

Will do!

I'll check when she gets home from work this evening and report back.

[elaw]

Um... I think the car needs a sensor?

As you can see in the attached VCDS log, the group 32 values are pretty reasonable: -0.9% idle adaptation and 1.6% partial adaptation.

But as you can also see in the attached log, mass airflow is zero! I may not be the world's leading expert on engines but I think that number should be greater than zero with the engine running, as it was. :wink:

I've heard MAF sensors tend to fail more when they're hot, and the car had been sitting for about an hour when I ran this test, after having been run for about half an hour on a hot day with A/C on.

And while I was sitting there watching the VCDS screen (actually I set it to log group 2), the MAF reading came back on, went to zero again, and came back again. I wiggled the connector but it didn't seem to make a difference.

So I'm thinking this is probably a bad sensor.

[rs4tech]

That would be where I would start. In my whole career I have replaced one set of 1.8t piston rings and that was because the customer severely overheated his engine and refused to have a replacement put in so he could keep his car "numbers matching" haha, so I did a complete rebuild after we determined he cooked his rings.

[elaw]

Yeah that zero MAF reading pretty much convinces me it's the sensor.

But what do you make of those leakdown numbers? Some of them were pretty lousy and as far as I can tell the leakage is all (or at least mostly) past the rings.

I talked to a friend of mine who's been working on European cars for years - initially Saabs but more recently German cars, and he's got me really spooked about sludging. He says crud builds up in the ring grooves causing the rings to stick, and in the pan which clogs the pickup causing low oil pressure which initially causes timing chain noise (did I mention the timing chain is noisy?) and eventually results in a seized intake cam.

What's your experience with sludging on these engines and what would you do if you suspected it?

I will say that under the valve cover is pretty clean - not clean enough to eat off of but nothing I'd call sludge. My friend says that doesn't necessarily mean anything and the only way to know for sure is look in the pan which is not exactly a 10-minute task!

[rs4tech]

I would strongly recommend replacing the oil pickup tube. They are very inexpensive and that is what causes the low oil pressure. The screen on the pickup clogs up and there goes the engine.

As far as the leakdown, what I would recommend is after doing the pickup tube buy two oil filters. Initially fill the engine with some high detergent break in oil along with some of gunk brand motor flush. Run the engine at 2k rpm for about a half an hour after getting the engine up to operating temp. The flush and the break in oil should clean up any sticking rings. Drain the oil and change the filter with a high quality European speck oil such as motul or total and enjoy many years of use from the engine, as long as you change your oil at least every 5k miles.

[elaw]

Is replacing the pickup tube a reasonable job with the engine in the car?

This engine has a chain-driven oil pump in the front, right?

I did some Googling and found a procedure for R&Ring the pan but the engine it showed had the oil pump closer to the rear of the motor. The guy basically had to disassemble the pump in place to get the pan out. Then when he put it back together, he had to reassemble the pump while holding the sealant-coated pan in position. Sounded like a bit of a nightmare.

[rs4tech]

It requires more than a bit of patience. You can get the pan in and out of the car without taking anything off of the pump, but you will need an engine support bar wince you have to lower the subframe in order to get the pan out

[elaw]

Ah okay. I think the writeup I saw kept the subframe in place and lifted up the engine.

[rs4tech]

No, lift the engine a bit and lower the front of the subframe as much as possible and it goes in and out, it is just a bit of a Chinese puzzle

[DE80q]

Gotta love needing specialty tools for things like this.

[elaw]

Heh... in this case most likely the "specialty tool" will be the engine support I built for r&r'ing the transmission in my Saab. It's a lovely thing consisting mainly of a 4x4, with 2x3 "feet" on the ends to rest on the inside of the fenders, an eye bolt to support the engine, and a winch for lowering the transmission to the ground. It's ugly and hard to store but it works!

[elaw]

Hmm... I notice ECS has an "oil sludge repair kit" that includes all sorts of goodies including a new pump for a fairly low price: http://www.ecstuning.com/Audi-B6_A4-Qua ... ES2718938/

...but at that price, I'm sure the pump is not an OEM one. Does anyone know anything about these aftermarket pumps (they don't specify which brand it is - maybe I'll ask them)? I guess the question is which is better, an OEM pump with 200K miles on it, or a brand-new aftermarket one?

Also it looks like changing the pump would be quite easy with the pan off... is that true?

[rs4tech]

Changing the pump is not difficult with the pan off, but not needed in my opinion

[elaw]

Re the MAF problem... I replaced the sensor last Friday, and the fault codes, warning lights on the dash, and black helicopters circling overhead have all gone away. So it appears the sensor was junk.

Today I'm taking the afternoon off work and I'm going to do an oilpanectomy on the car, look things over, clean what needs cleaning, and replace the oil pickup. I also had the bright idea that while I'm doing the job, I'm going to line the engine up between TDC and BDC and put a few ounces of motor flush down each spark plug hole and let the juice sit in there. I'll probably mix some oil into it so the cylinder walls aren't left bone dry when the liquid all seeps past the rings and drips onto my face as I work under the car...

Dumb question: is "break-in oil" a thing or will regular oil do? Can I get it at my local auto parts store?

[rs4tech]

Break in oil is a thing, most likely not available at a local parts store though. You may be able to buy a break in additive to add to regular motor oil, just remember that it is not meant to be driven on, just run in the engine for break in, so roughly 30min to an hour

[DE80q]

If you have a local speed shop, they will probably have break in oil.