Bigger than double DIN

A bigger write up later, but I had to share. This is a “double DIN” bezel/console — actually, VW Golf sized — from installed in a 2002 Audi TT, with a Joying JY-VL130 VW-focused Android-based head unit.

New Alternator

I had no idea alternators were so heavy. Dense little bastards, aren’t they?

Alternator change was mostly uneventful, except inconveniently placed — like everything else in this car. I followed this guide to get down in there. It was mostly uncovered during the timing belt work, but I really didn’t want to do the full disassembly, so the guide helped. While removing the vacuum reservoir tank (what the guide calls ‘the black canister’), I snapped a connector off the tank, which means that I had to replace the tank (8n0 131 541). Hooray plastic molding, and hooray Wolf Auto Parts.

Picked up a remanufactured alternator from Advance Auto Parts. Looks to be a rebuild in a Bosch housing. Everything lines up well and looks good, so we’ll see how long it lasts. I have the receipt if not. Bosch offers their own remanufactured units, but they don’t have any dealers in Minnesota, and don’t seem to sell online. Oh well. Out the door for under $130 for a nice looking, easily installed unit.

New on the left, old on the right. Have a weird feeling that the old one was original.

So, of course, this nice, new looking unit stands out a bit.


The big issue was that it would have been far easier to do while I was doing everything else, but I’m glad I did the timing belt beforehand. Reattaching the accessory belt blind, without removing the sound dampener or putting the car on jack stands was doable, but far easier when I remembered where everything was. The other issue was getting enough clearance without taking everything out that I had already taken out before. Most people seem to take out a vacuum reservoir tank that sits next to the passenger side headlight. Easy enough to remove — disconnect the hose tangle on top, remove one 13mm bolt, remove a vacuum line, remove. Except while trying to remove the self-clamping vacuum line, I broke the plastic piece it attaches to clear off the tank.


So, thanks Wolf Auto Parts for the quick delivery of a replacement tank. Pro tip – to remove this line, you can see the outline of a little button on the lip of this thing, about 1cm long, running along the lip. That has to be pushed in, and then the line can be removed safely and successfully. Save yourself the $35-$40 to replace the tank.

Needless to say, everything is a success. All my lights disappeared, and running voltage is perfect.

Timing Belt Service

After 3 years of ownership, finally had to do some real work on the TT, and when it rains, it pours — but more on that later. This Audi TT has one of the VW/Audi 1.8T variants, which means it uses a timing belt, and the replacement interval on these has dropped due to premature failure of the timing belt over the years. If the belt goes, so goes your engine — with bent valves at the very minimum. The manual states that it should be replaced every 105,000 miles, whereas the common knowledge now is 60-70k. I have no idea when it was done last, but if I’m going to do anything fun in the car, should probably take care of this.

The nice thing about owning a 15 year old car is that everything’s been done already by someone else, so I followed the excellent Timing Belt replacement guide by BlueTTop on the AudiWorld forum. I used the ECS Timing Belt kit with the Gates belt, and picked up a new Coolant Expansion Tank as mine was yellowed, and one 4-pin connector to replace a cracked housing on my 1st cylinder coil pack. Total replaced on the car included the aforementioned connector and coolant expansion tank, as well as the timing belt, accessory belt, tensioning pulley, tensioning dampener, water pump, and thermostat. For good measure, I also did an oil change.

I won’t go through every step of what I did, as the guide above did it far better than I, but just to highlight a few things…

Everything was dirty. This is almost-before, with the charge pipe removed, but most everything else still in place. Notice the very yellowed coolant expansion tank in the upper left.
Purchased an engine support bar from Harbor Freight for the occasion, as I’d have to either do that or get another jack, and felt this was safer if I had to buy something. Oddly, this was the most nerve wracking part for me, as I was so afraid of what would happen if something broke and the engine came loose. Note the trusty Bentley manual and what I’ve dubbed as “the tool tray” on the front of the car.
When draining your coolant, make sure the hose is on all the way, or you get a garage floor full of coolant. Doh.

The existing timing belt looks dry and old, but maybe the new one does already.
There is not a lot of room to work with these connectors, and I have a feeling this is already an aftermarket harness. The Lisle 57750 wire terminal tool kit from Amazon did a great job here, and way cheaper than the VW/Audi tool.

After everything was said and done, it sure looks a lot cleaner. I used Simply Green as I went to clean off parts as I disassembled and reassembled. I didn’t clean everything under the hood, as you can see by the battery tray, plastic surround, and some of the hoses.

Honestly, this was a lot of fun. It’s a 1-2 day job that took me about a month in between job and kids and time with family, but it was nice to just work on one piece at a time, especially when I needed something calming. There were frustrating parts — bolts that were nearly impossible to get to (hello, bottom thermostat housing bolt), missing tools (bought a torque wrench that only went up to 30 lb ft, while the engine needs 33 and 40, and the wheels need 89), things that didn’t make sense (is that supposed to spin or no?). There were also fantastic parts, like when the timing belt finally went on, every TDC mark lined up, and after a few spins, still lined up.

The test drive after went well, except for not putting quite enough coolant in. A new problem cropped up, though. On one of my drives, all of this lit up:

ABS, Brake, ESP, and Alternator. Not a good sign. VAG-COM doesn’t help me, as I have another persistent K1 Short to Ground issue that pulling fuses is not helping me track down. Battery is putting out 12.5, but testing the alternator gave me over 16V. I guess there’s the problem. Either it’s the voltage regulator on the alternator, or something else in the alternator, or both… Next up, replace the alternator!

New V6 rear valance!

In non-mechanical repairs, finally had a chance to replace two issues on my vehicle, and one looks pretty awesome. First one was replacing the passenger side lower grille, where most cars would have a fog light. It was missing, and there was just one big stupid looking hole in the front. Second, I replaced the rear valance (lower bumper, surrounding exhaust pipes) with the one that came with the upmarket V6 model. It wasn’t just for the look — at some point, someone rear ended this car, likely before I owned it, and it was cracked and snapped from the retaining bolts. I’m just happy I didn’t need a whole bumper.

It looks great. Ignore the fact that I’m in the reflection.

Adventures in “Going Elsewhere”

Just had to share.

I purchased the TT nearly three years ago, shortly after my son was born. Since then, it has gone to an actual shop once, and that was to do an oil change as we were mid move, and I didn’t have any of my stuff. When I bought it, the A/C blew cold air on a very hot day, which I was surprised and impressed with for a 165+k mile car. Unfortunately, by the next summer, it was gone.

I’ve tried a recharge kit, but the gas blew right out, leading me to believe there’s a leak somewhere. I bought a kit with dye, but the nozzle was too shallow for the low pressure port, so I got dye all around the port. Fine. I lack the tools or knowledge to do much of anything useful with air conditioning, so I brought it to a local shop to see if they could track down the issue.

They charge me $50 for the inspection, which I pay whether it gets repaired or not. I did not. Here’s what they found.

a) There’s a “big leak”, and they don’t know yet what’s doing it. My guess is that it’s the dye from my kit that they’re looking at, because if you listen to the noise of the gas leaving, it’s from the back of the engine, not the front. But, no dye at the back.

b) Even though they don’t know what’s leaking, they’re very sure I need a “freon temp sensor”, which will cost $108.57 for the part, and $96.60 in labor. Two issues. One, there’s no such thing as a refrigerant temperature sensor in the TT, only an ambient temperature sensor. There’s a coolant temperature sensor, but that has nothing to do with the HVAC. Chances are, they’re talking about the high pressure sensor which is in a static open state, which could be due to the leak *or* because the system is empty. Second issue, and this is minor, but stop calling it freon, as no car since about 1994 uses freon.

c) After they replace that, then they can evaculate and recharge the system for $172.62, and recheck to see where the leak is from.

In the end, they wanted $475.44 to diagnose, repair, and recharge, but no guarantees it’d work after.

I’ll just keep the top down, and worry about the switch later.

New intake

A little over a year ago, I decided it’d be neat to replace the intake on the TT, and while research brought me to the Modshack VTDA, they didn’t sell it anymore. I did find a K&N unit for a price I could afford, and made the switch. It completely replaced the stock airbox with a cone filter, a mini breather filter, and a big holder for the whole unit. It looked great, and sounded pretty awesome (extra woosh is better woosh), but there were two problems. First, it exacerbated a random CEL I was experiencing, and on longer trips, the wooshing got annoying, as I’m old.

Fast forward to today, and someone was selling a used VTDA on I jumped on it, and he shipped it super quickly. In a box, I got the VTDA… cylinder with a K&N filter inside, a mini breather filter, and some packing material. Browsed Google a bit until I found someone else who had installed it, and did the installation. Since the airbox already came out in the K&N install, the installation took me about 15 minutes, including a quick clean of the MAF sensor and devane of the MAF.

I’m super happy with how it looks, though the whole engine bay could use a cleaning, along with the VTDA. The best part, though, was the drive. It gave me the same level of breathing as the K&N did, but the sensor clean seems to have resolved my CEL and my hesitation, and the sound is still gently enhanced, but muffled a bit more so it’s not in my face when the top is down.
Highly recommended easy modification.
In the meantime, I never really finished project Audi Audio on the above, though I did take pictures. I may create a summary post, may not. Nevertheless, when I did the installation originally, I installed two amps to drive the speakers and the 8″ subwoofer. The sub was driven by an Alpine MRV-T320, and the speakers were driven by an Alpine MRP-F300. They both provided ample power for the installation, but I was always bothered by having two amps throwing off heat in the cramped shelf of a trunk of a roadster. I replaced those two with a Precision Power P900.5 five channel amplifier this weekend, and what a great replacement. The sound quality is great, the unit is super compact but still throws out the power I need, and it doesn’t give off more heat than one single of those Alpine amps.
I’ve also been working on cutting and moving things to make the TT head unit a double DIN unit. I started with a Nexus 7 install, but got frustrated with how finicky it was in terms of powering on and resetting, so I grabbed one of those inexpensive Chinese Android-based head units, since I have to custom cut anyway. I’ve completed the wiring, and cut the radio frame appropriately so that it’s mounted, stays there, and works well. I’m in the process now of altering the bezel to make it look like it belongs, and I’ll post progress there later.

Project Audi TT Audio: Head Unit

I always felt that the head unit was the easiest component of most vehicles to replace. Modern vehicles have hugely custom setups, some controlling HVAC and car preferences, which makes it a pain. Luckily, in this case, the only sin is that Audi uses a slightly wider faceplate on their head units. I actually replaced my head unit last fall as the original Concert unit was failing, so there’s going to be some stuff from memory here. I grabbed parts as required for the first installation, however, since I’m bypassing the Bose amplifier now, it’s possible that we can go for a cheaper wiring harness.
  • Metra 70-1787 Radio Wiring Harness for VW/Audi – Bose
  • Metra 40-VW54 Amplified Antenna Adapter


Wiring Harness and Power

I had to modify the wiring harness before as the pinouts didn’t match what the TT was bringing out at all. The yellow power lead didn’t connect to anything, and it required me to pull pins out and replace them elsewhere. For this install, I yanked everything else out. So, you’ll only need the black harness, providing power, as everything else is for either audio output or the amp remote wire, which isn’t necessary, as I’m disconnecting the Bose amp. To be clear: You’re getting constant 12V power via the yellow line, and ground via the black line. Switched power has to be tapped.

To tap switched power, I went under the driver’s side again, and ran a wire from the 30X terminal on the far left side of the power bar directly under the steering wheel. It does what it needs to do — it’s on when the key is on, it’s off when the key is off, and it provides 12V. I wouldn’t power anything more intense than a head unit off that line, but it works really well for this purpose.

For FM radio to work, the 40-VW54 adapter is just connected to the separate antenna connector in the TT, and the blue line is connected to either the amp remote or antenna remote of your head unit. The Sony head unit I purchased had two separate leads, so I could connect the amp remote to one, and the antenna remote to my adapter. If the head unit doesn’t have separate leads, connect both the amp remote and the 40-VW54 to the amp remote lead of the head unit. If one were using the original Audi head unit, you could wire it into the amp remote line on the red wiring harness in the above Metra kit.

Audio Line Out

Project Audi TT Audio: Amp Power

I’ve installed amps in vehicles all of twice, and both of those cars were not German. One was a 1997 Dodge Intrepid, and one was a 2001 Mitsubishi Eclipse Spyder. The Intrepid was fairly easy because it was huge and had a lot of open spaces, so finding a place to drill wasn’t terrible. That said, I made someone else do the drilling, as I was 18 and stupid, but not stupid enough to ruin my only car. The Eclipse was easy because the thing was a tin can and you could route wires through any of the wide open, uninsulated spaces in the whole car. I hated that car. Anyway, since the Audi is getting a whole build, I elected to start taking stuff out of the car first, to make the process (theoretically) easier. First, I yanked out the head unit, and then pulled out the seats. Well, first first, I disconnected the battery. Let’s not be ridiculous.
Audi recommends the use of an adapter of sorts when removing the seats from the car, to prevent the airbags from going off. Dr. Google seems to have the opinion that this isn’t required if you’re doing this in a space where static electricity isn’t much of an issue. I ran with that, pulled four bolts from the bottom of each seat with an allen wrench, disconnected the three wire harnesses underneath, and put the seats aside. This gave me plenty of room to work in the car. Note that there isn’t a lot of room under those seats to remove those clips, and they fasten on the top and bottom. I ended up using a flathead screwdriver to lift one clip while wiggling it out. It helps to unbolt first and then rock the seat back to get more room to work.
After that was complete, I pulled out the lower dash panel under the steering wheel. To do that, remove the cover of the fuse box, which you’ll see if you open the driver’s side door, and look on the left side of the dashboard. Those are just push clips, so it’ll pull off if you slide a flathead under and pull outward gently. There are two hex screws on the lower curve, and then one nearly dead center, that is inset somewhat, as it’s bolting in the dash cover and not the outside of the fuse box. Then, underneath the steering wheel, there are two hex screws on the bottom that need to be pulled out. The dash cover can then be pulled straight toward you from the steering wheel, and then downward. You’ll want to pull the wiring from the headlight switch and from down below, and then you can pull the whole thing out, if you want.
Once you’re done, you’re left with this:

I started with the guide on Waks Wide Web, the defacto source of garage how-to for the TT, to run the amp power cable. The guides on that site assume a RHD UK TT, so when he mentions “glove box”, it’s under the driver’s side for the US. I also ignored everything about the remote wire, since this is being controlled by an aftermarket head unit with a dedicated remote lead. I was stumped with what I saw there. First, the box that can “easily be unclipped and moved to the side” is either the thing on the left or on the right. The thing on the left provided no more visibility or ease to me when it was unclipped and moved. The thing on the right wasn’t going to budge for anyone or anything. So, I tried from the inside. He talks about the big loom, so I found that above the dead pedal, taped my 4-gauge power cable to a wire hanger, and tried to push it through.

Nope. Not going anywhere.

So, I’m shining a flashlight behind the engine. I pulled out the airbox entirely (which came in handy later), to see if I could see another hole with more room. I’m shining a flashlight all around under the driver’s side, and I’m starting to get ready to find a place to drill, or try to remove the white covering that is all along the firewall on the inside of the car, thinking maybe something is covered on my car that isn’t covered on others. Then, as usual, it was actually staring at me all along. There’s a dime to nickel size rubber grommet almost directly above the gas pedal. I pushed on it, it came out, and I could see the light from the open hood of the car. Success! I took my taped cable and ran it through that hole until it it something.

It comes out somewhere around that box that Waks Wide Web was talking about. Mine poked through the heat shield behind the engine, but I pushed it back and routed it to the right hand side. In a perfect world, this would run along the wire track that you see on the right, but as I mentioned before, I have no idea how to gain access to it. I successfully unclipped it from the bottom, but without getting to it from the top, that’s useless.
I kept the cable below the airbox, covered the cable, and put the airbox back into the car. I’m not attaching it to anything yet, but now I know my cable length, and I know where it’s going. Insert a new grommet so the metal is not rubbing against the cable, and put some sealant on there so water doesn’t get in the cabin.

Project Audi TT Audio

So, last fall, I picked up a 2002 Audi TT 225 Roadster with a little over 160,000 miles. It’s super high mileage, but drives super well, and I figure it’s a great little car to learn on. Luckily, nothing terrible has happened yet, but I can guarantee you that this car will be featured more than once on this blog in the near future. Once winter came, the convertible was in the garage quite a bit, and I noticed that after a couple of weeks, the car needed a jump start.

Super annoying.

After some considerable trial and error using the fuse box, turns out that it’s the Bose amplifier that is causing a pretty big power drain while the car is off. Not a big deal if it’s driven every few days, but significant enough that it’s dead after about a week and a half. Well, go big or go home, right? Instead of picking up a new amp to provide the same lackluster sound, why not spend a little more and redo all of the audio? I have the Bentley manual, how hard could it be?

I love bad ideas!

So far, on the build list:

  • Sony DSX-S310BTX for the head unit
  • Alpine MRP-F300 4-channel amplifier to drive speakers
  • Alpine MRV-T320 2-channel amplifier to drive subwoofer
  • Alpine SPR-60C 6.5″ Component speakers for the doors
  • Infinity Reference 4032cf 4″ 2-way speakers for the rears
  • JL-Audio 8W1v2-4 8″ Subwoofer for the rear
  • A boatload of Dynamat, cabling, and fuses

I’ve already started the project, slowly but surely, as I have an infant and a job, so I’ll be updating with some of the ridiculous crap I’ve dealt with so far, and continuing from there.