My 1999 Audi A6 Avant is a nice old car. The emphasis however is on old and that means it needs a good bit of attention to keep it happy. Here’s what that entailed this year, along with a handy Pain-In-The-Ass scale for each.

Do you remember the story about Goldilocks and the Three Bears? Aside from the white entitlement exhibited by the primary protagonist, one of the tale’s main takeaways is admonishment of extremes. Nobody likes things that are too much this or excessively all that. No, most people like things to be—as baby bear so eloquently laid it down—just right.

Now, as cars get older, they go through a phase that is the exact antipathy to what went down in Bear Senior Esq.’s abode. New cars tend to have fewer problems, and cars that have reached a ripe old age can be considered classics and are given a pass for any maladies that may afflict them. In the middle however, are those cars that are just plain old, the ones that tend to offer the greatest frustration when they throw a tantrum.

I have just such a car, a 1999 Audi A6 that we keep around just because we like it so much. We’ve had the car for about three years now. It was purchased from a distant relation through marriage, and I initially gave it to my daughter to serve as her daily driver. She freaking loved the car. I mean let’s be honest, it’s pretty posh.

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Eventually my daughter got a new job that required some substantial drive time, and putting premium gas in a car that averages about 20 mpg got old really fast. She bought herself a newish car and we got the Audi back. Over the course of our our combined usage we’ve put about 24,000 miles on the car. It now has a little more than 152,000 in total.

It’s been a pretty reliable ride over those miles too, but I wouldn’t exactly call them trouble free. In fact, I’ve done quite a bit to keep it going. Here’s the tally so far for this year. I’ve also included a handy metric for each project that I’m calling the Pain-In-The-Ass scale. That will give you an idea of just how hard each task was to complete. This list is chronological. Let’s get started.

January—Heater Hoses

Oh. My. God.

Heater hoses are considered consumables, and hence they should be fairly easy to replace, right? Well, on the C5-generation A6 they’re not.

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The problem started with a frantic phone call from my daughter, who was on her way home from work. “There’s smoke coming out from under the hood!” That “smoke” turned out to be steam, and the issue was that one of the plastic connectors for the outbound heater hose had given up the ghost.

I made the 26 mile trek down to her place in our creaky old van and, after a trip to Pep Boys, was able to rig up a fix that allowed me to get the car all the way to my driveway where a proper repair could be affected.

Now, you might expect that heater hoses are a snap to replace. A couple of hose clamps, a little grease on each of the fittings, and Bob’s your uncle. Well, Bob is most definitely not my uncle.

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The snood sits to the right of the battery and your life will be much improved if you remove the battery when doing this job.

A feature of the A6 and related VAG cars is a mezzanine-style firewall. Above the back of the engine bay is a log-style box in which sits the battery, brake booster, cabin air cleaner, and the pass-through for the heater hoses. Those hoses are S-shaped, like the snake that haunts your dreams, and drop down through a hole in the bottom of the box, sealed by a rubber grommet.

The hoses connect to the heater core at the firewall proper, in between the brake booster and the battery. The whole thing is covered by some sort of modesty snood with snaps underneath.

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That doesn’t look too hard, does it?

That end wasn’t too tough, the only issue being that someone had previously installed the clamp on the lower hose so that the screw fitting faced the brake booster and was nearly impossible to undo.

It was the other end—the busted one—that was a challenge. That was because neither of the engine side hose connections were visible and I had to Ray Charles my way around them. The connections are pretty simple snap on fittings with a spring as a retainer. The thing of it is, both of the hose connections were stuck on tenaciously, and like arguing with my wife, I had no leverage.

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This is what the hoses look like when they’re not in the car.

I was able to twist the intact hose and fitting enough to break it free, but the broken fitting demanded that I saw at it with a reciprocating saw blade held barehanded with my arm getting cut up on the sharp edges of various connector mounts and screws above. Thanks, Audi.

That’s the connector and the hose bib. Sorry it’s out of focus but I was taking the picture with my phone dangling down behind the engine.

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Once I got the hoses all hooked up and the system full of that funky pink coolant, we were good to go. Overall the project took two weekends since I needed to diagnose the problem through partial disassembly on one, and then wait for Rock Auto to ship me the new hoses for installation the next.

Pain in The Ass (PITA) Score—1 to 10 with 1 being no sweat and 10 being just kill me now:

8.5—Let us never speak of this again


January—Front Brakes

I like doing brake pads. Hell, I could do brake pads—front or rear—in my sleep. I have a cool little tool that will ratchet back the piston on systems with parking brakes and that makes the job a breeze. What I don’t like is being told I have to do brakes and that’s just what the Audi did this past winter.

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It’s my own fault for not having noted when I did the brakes last, but that didn’t stop me from thinking I had just done them and hence equating the pad warning light and annoyingly loud beeping from making me think it was a sensor error.

You wanna come over to my pad?

Well, the error was mine, as you can see from the picture above. That little groove in the pad is where the wear sensor goes and since it’s gone, the pads did need to be replaced. I ain’t even mad.

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PITA Score: 2.5 — I did have to jack the car up and take off the front wheels


February—Spark Plugs

At around 150,000 miles I figured it would be a good idea to change out the plugs. I mean, it’s a cheap way to ensure maximizing performance and economy. It’s also a pretty easy job on Audi’s longitudinally-mounted V6, once you remove the plastic vanity covers.

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It was nice or Audi to number each plug wire for me.

Then all you need is a really long extension and a spark plug socket that’s got enough grip to hold the plug during the elevator ride up or down the hole, but not too much that it too gets stuck down there. Luckily, I have a pair of forceps in my toolkit that worked wonders at pulling the stuck socket out.

Be forewarned before visiting: I anti-seize everything I can get my hands on.

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The plugs went in with little issue and the wires looked to still be in decent enough shape so I left them alone. The only problem was with what I discovered while undertaking this task. I’ll cover that next. First however:

PITA Score: 1.5 — The plugs sit way down in their silos and with the wrong tools could get mucked up


February—Cam Cover Gaskets

As I noted, changing the plugs brought to light a fairly sizable issue, which was the failure of the cam cover gaskets. This results in oil leakage which is bad enough, but can also cause misfires when the plugs short out as they drown in their wells.

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Another visit to Rock Auto’s arcane but serviceable website brought new gaskets right to my door. Unfortunately for me, I mistakenly thought I was ordering two sets but only in fact had only ordered one. That mistake quickly rectified, I got to undoing each cam cover and replacing the dried and leaky gaskets with the supple and seal-keeping new ones.

Removing the airbox provides plenty of room to work. Hell, I might just move in there.

There are two main gaskets to replace here, the one that follows the lip of the head and another that seals the three spark plug silos. There’s a total of about 8 fasteners on each cover and getting them torqued down properly is critical.

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Note the bump on the back end of the intake cam. We’ll be revisiting that in a bit.

This was also an excellent opportunity to examine the wear patterns on the cam lobes and chain tensioners. Luckily everything seemed to be in fine shape.

Fun fact: the left and right side heads on the Audi 2.8 are interchangeable. They just sit backwards of each other on each side.

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Sealed up and with the perfect amount of orange gasket seal the fix stopped the leaks and minor misfires the engine had exhibited. All in all a pretty easy and satisfying job.

PITA Score: 2.5 — Aluminum heads and proper torque meant a bit of nervousness during reassembly


June—Cam Position Sensors

At the dawn of the automotive era most engine management was controlled by two main sensors: the driver’s ears and/or his or her ass. The former could detect subtle changes in engine sound which could then be addressed by manipulation of manual controls for things like spark advance and throttle opening. The latter could offer tactile evidence of rough idle or flat tires.

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Today however, we have computers to do much of that work and those are fed information by a multitude of engine monitoring sensors. Should any of those sensors go the way of Elvis, engine performance, either in output, emissions or both might be negatively impacted.

You might not ever know that something has gone wrong were it not for the very same car computers which can tell when a sensor is providing out of range data, or none at all. Of course, the way the computer typically let’s you know this is through the dreaded CEL or Check Engine Light.

A couple of simple spring clips are all that separate me from the bad sensor.

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I got a CEL on the Audi back in June. A quick code pull with my ODII reader showed that the cam position sensor on the left bank was reading insufficient voltage. After the requisite shoulder slump of resignation, I did a quick check online to see if I could source a new part, or if I’d need to pull one off a junker at the yard.

Amazingly, Amazon had the sensors for about ten-bucks each brand new. Naturally, I bought two. The front sensor is remarkably easy to replace. This proved a refreshing change from other seemingly simple fixes like the thermostat that require removal of the entire nose of the car to replace.

This is the cam-side of the hall sensor, a cup with an opening to trip the magnet on the other side.

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In the case of the left-side sensor, the cam cover needs to be unsnapped and lifted away, exposing the two screws and electrical connection that connect, physically and electronically, the sensor to the engine. The sensor itself is a Hall effect sensor that’s fitted over a camshaft-mounted cup. Replacement is literally a five minute job.

Old... and New The sensor is in the top-right corner of each.

The same can’t be said for the other sensor. This one sits in the back (remember I noted that the heads on the 2.8 5-valve are interchangeable but backwards?) and while it’s also two bolts and an electrical plug, there’s a water hose that connects to a block bib right behind the sensor. To remove the cam position sensor you have to remove the hose and that means potentially losing some of that pretty pink coolant if you don’t clamp it first.

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Hipster bar lighting.

Once I had both sensors in place I cleared the OBDII code and confirmed that the CEL wasn’t coming back. It didn’t, but the car now needed to run for about 250 miles before the system would clear the car for emissions testing and my tags were coming up in July.

That meant switching to the Audi as my daily driver, a sacrifice I really had no issue making. After about two weeks of that, my reader gave the car a green light for smog. With that I took it to a station where the A6 passed with flying colors while I stood by and watched France beat Argentina in the World Cup finals.

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PITA Score: 2.5 — The left side was a breeze. The right side was kind of a little bitch.


July—Brake Flush

Remember earlier we looked at doing the brake pads? Well, those are only one consumable in an automobile’s braking system. The other is the brake fluid. It’s hygroscopic so over time it can absorb water, and can also get contaminated with other impurities. After all, an engine bay is a dirty place in which to live.

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The canister creates positive pressure, which pushes the fluid in the master reservoir all down the lines.

I did the fluids on the Audi using a pressure pusher. This is a pressure container that is attached to the brake fluid reservoir via a rubber gasket cap and pushes the fluid through the system where it’s captured in containers at each of the calipers. Easy and peasy.

The brake fluid goes round and round (whoa-oh) and it comes out here.

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You can also go from one fluid color (amber or green) to the other to ensure you’ve pushed out all the old stuff.

PITA Score: 4.5 — The process is easy, but the kit costs about $65 and you do need to pull all the wheels off


July—Power Seat Switch

Okay, this isn’t technically something I needed to do to keep the car on the road, but after having accidentally kicked the power seat switch on the driver’s seat (don’t ask me how) I did feel the need to fix it. The switch came from a junker in the Pull-It yard.

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The hardest part is figuring out how to pull the plastic cover off without inflicting even more damage.

PITA Score: 1 — Two knurls, one cap.


July—Cruise Control Vacuum Plenum

Another job that wouldn’t prove necessary to keeping the car on the road but which was a nice little victory was the cruise control actuator. When I was replacing the heater hoses I noticed a largish open hose that looked like a vacuum line. I traced the connected end of it back to a vacuum pump and realized that it was for the cruise control. The question then was, where did the other end go?

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I eventually discovered that it attached to a vacuum plenum that bolted to a bracket just above the throttle body.

Apparently sometime prior to my ownership someone had removed that vacuum plenum and the little arm that connected it to the throttle and had for whatever reason, never put it back. Great.

That part was made by Hella and was used across a number of makes and models, including Jags and Land Rovers. Despite that seeming ubiquity, it’s presently damn hard to find and can be expensive when you do.

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I had a bit of a coup one day when visiting the junkyard as I came across two cars with the unit still attached. I bought both. In fact, I now pull each and every one I can get my hards on since they go for a good bit of change on eBay.

Hella good time. The vacuum hose fits on that open tube on the top.

After testing the ones I bought, I bolted and hosed one into my A6, and now I have cruise control... something I pretty much never use.

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PITA Score: 1.5 — The throttle connection is a press fit, but is really an awkward reach to get in place.


August—Struts

Do you suffer from motion sickness? You know, like from the rocking of a boat, or rolling down the highway in a car with tired shocks? I don’t, but that doesn’t mean I like wallowing when I drive.

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The Audi’s struts were those that were originally installed at the factory, and at nearly 150,000 they were done. I decided, since obviously I like doing things that aren’t 100 percent necessary, that I would replace them, front and rear.

William Stein, but you can call me Bill.

Now, I probably should have pointed this out earlier, but I don’t have any sort of manual for this car. I pretty much just wing the wrenching since I kinda-sorta-know what I’m doing in the general sense. That being said, I usually try and see if there’s a YouTube video of any repair I’m attempting so I can skip an ad in five seconds and then get the gist of what I’m about to do.

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There are far more bolts that you have to loosen than remove to extract the rear struts. It’s vitally important to mark the position of the lower arm locator to ensure proper camber upon reassembly.

For the rear struts on an Audi A6 Quattro, no such video apparently exists. Thankfully I was able to gather all the torque specs online for when I started to put things back together. I also had a pretty good idea of how the Quattro rear suspension worked so I did know to mark all the appropriate cams and positions so I could get everything back together correctly.

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I use both marker and painter’s tape to mark alignment on struts when I take them apart since it’s always a puzzle getting them back together.

Since I really was figuring this out on my own, I’m a little cowed to admit that the left side rear strut took me the better part of a day to replace. Once I had it down, the right side took less than two hours.

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The fronts were a similar situation, if a little simpler. The multi-link suspension needs to be unbolted from up above and below, and then the whole thing gets slotted out through the wheel well. A couple more nuts reveal the strut mount and then the spring compressors can be applied.

It’s common for the pinch bolt to be rusted in place, but mine came out without issue.

The biggest issue with the front suspension is Audi’s choice to have the lower strut bolt face forward requiring the removal of the rear locator arm for its extraction. Why not the other way around, Audi?

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For those of you frightened by the prospect of compressing car springs, let me tell you, it’s well warranted and I’m right there with you. It’s one of my least favorite things to do. Fortunately, after several years and a number of cars I amazingly still have all my fingers and sight in both my eyes!

The front suspension took me about two hours per side, although I stretched the job out doing one on Saturday and the other on Sunday. The old struts proved to be completely shot, as they offered almost no resistance on compression and absolutely zero rebound.

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Once everything was torqued back in place the difference in ride quality was immediately evident, as was a newfound quietness where graunches once proved common. All in all, a very satisfying, if grueling job.

PITA Score: 6.5 — Once you know what you’re doing, it’s not hard. You do have to compress some big-ass springs, and that can scare a lot of people off the job. 


Wrap up

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Well, that’s it (touches wood) for the car so far this year. Since doing all that work—and it was a lot of work—the car has passed its smog and continues to be a wonderful car to drive. There still are a few issues, but nothing to seriously dampen its enjoyment.

The question I now have is what to do with the car? I really like having it, but I don’t really need it and I have a number of other project cars that really could benefit from my attention. Still, I think for now I’ll just hang on to the A6. In fact, maybe I’ll go right now and take her for a spin.