Fascinating - Audi and MB issues

[pauldun170]

pulled from ttac

Geeky1April 1st, 2010 at 5:46 pm
*eyeroll*

I serviced them-both Audis and Mercedes-for 3 years and my relatives have a W221 S600. Between myself and the rest of my family, we’ve also had a W220 S600, a W220 S500, a W140 S500, two 560SELs, a 6.9, a 350SE, a 300SEL 4.5 and a W111 chassis 250SE. Nevermind the Es and SLs we have/had. The only cars that Mercedes has made in the past 40 years that have been truly problematic were the W163 M-Class SUVs.

Anyhow. The W220 was a solid car with the exception of three issues:
The ABC and Airmatic suspensions were both leak-prone, the 3 valve V8/V12 engines will develop oil leaks @ the oil pan gaskets, the valve cover gaskets and a small cover plate on the timing cover below the oil filter housing, and the crank position sensors have a nasty habit of failing without warning, usually between 60,000 and 100,000 miles, and more often than not they do leave you stuck when they fail.

They do occasionally lunch their airflow meters, but it’s more of a “yeah, another E320 we had in 6 months ago did that too” thing, not an “oh, yeah. No problem, we have the MAF for your A4 in stock, this is the 4th one we’ve done in the past 3 days” thing.

The W221s that I saw had no real issues (albeit possibly because they were still newer and relatively low-mileage cars when I /quit), and our S600 has been absolutely flawless.

Audis, on the other hand… Oh let’s see. Let’s start with the engines, shall we?
1.8T:
-Premature failure of water pumps leading to timing belt service intervals along the lines of 70-90k miles instead of 105k
-Premature failure of thermostat leading to same
-Sludge issues caused by ineffective and ridiculously complicated PCV system-which itself becomes sludged up and quits working, leading to oil leaks-and a laughably small oil capacity (4.5qts? please) and an overly long oil change interval
-Timing chain (only one cam is driven by the belt, the other is driven by a chain connected to the first cam @ the back of the head) tensioner failure due to oil starvation caused by sludge issues even when following recommended maintenance intervals
-Timing chain tensioner gasket failure leading to oil leaking down the back side of the head and the block due to excessive crankcase pressure caused by a failed PCV system
-Spends more time with the CEL on than off due to MAF failures, oxygen sensor failures, coolant temperature sensor failures, and vacuum leaks
-Oil coolers and coolant expansion tanks are both prone to leaking coolant, as is the plastic flange at the back of the cylinder head

It’s worth noting that the tensioner gasket is usually done with the valve cover gasket, and that the job is 4.5 billable hours. The PCV system is usually done at the same time since it’s plugged and most of the rubber hoses are oil-soaked and falling apart/spongy; there are a total of 30 parts that are replaced during this service, at a cost of something like $400 (it’s been a few years) and another 4.5 hours in labor. Oh, and the timing belt service is about 5 hours, since the recommended procedure to R&R it involves removing the entire front clip on the Passats and A4s or finagling it through the passenger side wheel well in the Beetle/Jetta/Golf. All three of these issues typically come up at about 80k miles (give or take 20) and the total cost to address all 3 is in the ballpark of $3k with labor costs being what they are in this part of the country (about $125/hr, $200/hr @ the dealership).

2.7T:
Most of the same issues as the 1.8T; doesn’t have a coolant flange at the back of the heads to leak as far as I recall, and it doesn’t have any real issues with sludge, but other than that all of the issues are the same. And it’s more expensive to fix than the 1.8T; the chain tensioner gaskets on this are 7 billable hours.

2.8:
1.8T, round 3. No sludge issues as it’s not a turbo, but the PCV system is still garbage (at least on this engine it’s only a plastic hose across both valve covers and a couple of small rubber elbow hoses at the back of the intake manifold that need to be replaced), it still eats vacuum hoses and airflow meters and it still pisses oil all over the place.

4.2:
An’ here I go again on my own… Goin’ down the only road I’ve ever known… Like a drifter I was born to walk alone…

Ehem. It’s the same old song as the other three; oil leaks from every conceivable orifice, coolant leaks out the wazoo. Not quite the same appetite for MAFs as the 2.8 and 1.8, but they still go through them.

Compare that to the MB engines, which suffer from oil leaks and consistent failures of crank position sensors every 60-100k. They have no other common issues of any kind; the aforementioned airflow meter issue is not uncommon, but it’s not so bad that it’s possible to predict exactly what’s wrong when someone calls and says “the check engine light is on in my 2001 E320″ the way it is when they call and say “my 2002 A4’s check engine light is on again.”

And remember how timing belt replacement on Audis is often hastened by water pump failure? In 3 years I replaced one water pump on a ML430 with 165,000 miles because it was leaking, and did one precautionary replacement on a 1987 560SL that had 140,000 and had a slight amount of dried coolant (literally, just a few drops) below the weep hole.

And while BMW engines typically suffer from cooling system issues-and they’re arguably more severe than the Audis as BMWs like to eat their radiators and hoses as well as the water pumps and thermostats-replacing a water pump on a BMW isn’t usually a living hell of insane labor charges the way it is on the Audi engines, so it’s not really as big of a deal. And what other issues to BMW engines have? You mean besides valve cover and occasional oil pan gasket leaks? For the most part, nothing. Some have VANOS issues, but that’s about it.

I didn’t get to see many of the 2.0/3.2/4.2FSI/5cyl VAG engines before I left, but of the handful of 2.0Ts that I DID see, all of them already had PCV issues at less than 50,000 miles. The more things change, the more they stay the same, as the saying goes.

Now that that’s out of the way, let’s look at the rest of the cars, shall we? Let’s start with the transmissions. In 3 years I replaced 4 Audi automatics and 3 manuals. All of the cars had less than 100,000 miles on them. I replaced 2 Mercedes 5G-Tronics; both cars had over 150k. Never replaced a BMW transmission.

How about the rest of the drivetrain and the suspension? Try asking me how many times I’ve had to sell a rear output shaft reseal on a transmission in an A4 or A6. I won’t be able to tell you, because I’ve lost count.

Likewise, I don’t remember how many times I sold a complete rear diff reseal, which is a labor-intensive and expensive job, and one that’s especially painful to quote on certain A4s because the ETKA diagrams that show the rear diff leave out a seal or two that you need to do the job. You try ordering a part from a dealership that you don’t have a part number for and which doesn’t show up on the factory illustrations sometime. See how far you get. Total cost is about $1500 on most Audis.

I’ve replaced driveshafts in a couple of A4s and A6s as well; never had to do that in any of the BMWs or Mercedes we saw except for on a single 1987 535is that had 225,000 miles on it.

And what’s up with the whole split a-arm thing on the Audi front suspensions? They use 8 control arms on the front end of the A4/6/8 because it supposedly allows for more precise control of camber angles when cornering. That’s great. Awesome. Mind you, it doesn’t help any because the cars are still godawful understeering pigs, but at least it works on paper. Problem: They fail all the damn time. I can’t recall seeing a single A4/6/8 make it to 100,000 miles without replacing all 4 front upper control arm assemblies ($1200) due to cracked bushings, loose ball joints, or both.

Some BMWs have issues with control arm bushings as well, but they’re less common and typically less expensive to fix than the Audis. And this is mostly a non-issue with Mercedes vehicles; the W220s have a funky front suspension design of their own that does cause premature bushing failures, but it’s typically at a higher mileage (100k+ vs. 70k), it doesn’t happen as often (say about 75% of cases vs. every fecking Audi I’ve ever seen), and it’s the only Mercedes that I can think of offhand with any kind of issue with premature failure of suspension components.

Know what else the Audis go through like a cop through a box of krispy kremes? Tie rods. 9 times out of 10, by the time your control arm bushings are shot your tie rods are ready to retire, too. Neither BMWs nor Mercedes do this.

Oh let’s see… that’s most of the basic mechanical stuff covered, what other issues do Audis have that their German counterparts do not? Oh yes. Interiors.

They look great when the cars are new, but between the dye or paint or whatever it is that they use on certain plastic parts like the door handles (not the lever you use to open the door, but the handle itself in the door panel) wearing off and entire lines of pixels in the information display failing, by the time they’ve seen 5-6 years they look like hell. Sure, the digital displays in BMWs and Mercedes fail sometimes too-the late E32/early E38 7 series, the E34 and the E36 are all famous for it, and it’s not unheard of in some Mercedes (particularly the W210 and W203) either. But it happens a hell of a lot less often in the Mercs than it does in the Audis, and the BMWs are going on 20 years old. What’s Audis excuse?

And then there’s parts availability; it’s not yet an issue on the cars that the OP is looking at, but it bears mentioning anyhow. Last time I checked (a few years back), I could still order a set of brand new floor mats for an M1 from BMW. Hell, BMW rebuilt an entire 2002 using largely new or NOS parts a few years back as a publicity stunt. And I can still call Mercedes and order parts for a 1962 190SL (incidentally, one of our customers DD’d a 190SL for more than 40 years; the car has over 700,000 miles on it, the engine burns little oil, has decent compression and has the original head gasket. Find me an Audi that’s done that. I can dig up Mercedes that have all day long, all I’m asking for is one-just one-Audi that’s managed to hold its **** for that long. You won’t find one.), if not through the dealership (though some parts are still available that way) then through MB Classic. VW/Audi? ROFL. Not a chance.

Hell, there are some parts that are NLA for the Audi 4000. The thing isn’t even 30 years old. I can buy parts for a Mercedes going on 50, but an Audi from 1985? Sorry. One of the last jobs I dealt with before I quit was an early 90s GTI. I forget what year, but I want to call it a 1991. 2.0L/8v. The car had a little switch on the throttle body to detect WOT or some such. The switch on this guy’s car had failed, causing it to surge and generally run like crap (well, crappier than the 2.0 usually runs, at least). Called VW with the part number to order a new one. No longer available. Part had been discontinued. Called Audi to see if it was used on any of their cars. Also NLA. And none of the wrecking yards I called had the correct throttle body for the car. That thing wasn’t even 20 years old and it was already unfixable and undriveable without a little bit of backyard engineering. That right there should tell you all you need to know about how VAG views their cars.

Owning a VW or an Audi out of warranty is a mistake that most people only make one time. People that do it more than once, on purpose, are either masochists, intellectually challenged or insane.