The Audi of Destiny

The low-coolant leak alarm screamed at me today. The fluid level was below minimum. I checked underneath immediately after parking and it’s dripping fairly rapidly somewhere in the rear of the engine compartment. D’oh.

Cruise refuses to work. I checked the vacuum hoses under the hood and they’ve all deteriorated. VW/Audi insists on using cloth-braided rubber hoses for this application, when silicone would work so much better. My brother has some leftover silicone tubing, so I’ll try that sometime this week. If this doesn’t work, I’m replacing the cruise computer.

O’Reilly found that one of the rear shocks burst a seal and it sprayed oil all over back there. I’m taking it in with a replacement this Wednesday.

Okay, the cruise still doesn’t work. I checked the Bentley manual, which has a wiring diagram. I wired up the resistors to the brake lights and… nothing. Next is to try resetting the computer through VAG-COM.

Note to self: Make sure you splice the right wires when installing a load resistor. Now the right turn signal doesn’t work when the brake is engaged. Easily fixed. Maybe. The good news is that the brake lights are brighter than conventional now.

I installed a pair of high-intensity LEDs for the brake lights. These also came with load resistors which should simulate conventional incandescent bulbs to the computer. LEDs show up as a dead bulb because they draw so little power. I also converted the third brake light.

The advantages to LEDs are:

• don’t burn out unless you overload them
• draw very little power
• virtually instant-on

The only disadvantages I can see is that they’re more expensive.

When I last had my A4 in for service, they told me the rear bearings were loose. The estimate was ~$400, which seemed steep. Well, lately I noticed my car wanders a bit going down the road and it’s been getting worse. Also, the brakes have been making a low-speed grinding noise as I come to a stop. I guess I’ll have to grit my teeth and get the work done.
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Just got two of the oxygen sensors replaced this week, along with the fuel filter. Grand total: $881.37 with tax. Good news is, the fuel economy is back to where it should be. It won’t take long to justify the cost with gas prices the way they are lately.

Next project: brake upgrade all around.

The robins are here, the grass is green and my wheels have been mounted with new tires.

This winter has been the coldest in years. As the temperature gets closer to 0°F, the A4’s engine behaves erratically. Sometimes the idle sticks around 2700RPM. Other times it just leans out and dies. I found that if I turn down the fan speed on the heater, I don’t have any problems. It seems that the heater core over-cools the system enough where it confuses the engine control system. If the temperature gauge is just one notch below center, that’s enough to cause problems. It sets off the check engine light, which when decoded shows as an air intake leak.
There are a few possible causes for this:

1. Throttle body might physically stick when it gets that cold. A cleaning and lube would help that.
2. Oxygen sensors have never been replaced. At 184,000 miles, they’re probably due. Too bad it’d cost over $1000 to replace all four(!) of them.
3. Idle stabilizer is malfunctioning when cold. This is possible, since it runs off of vacuum pressure.

For now, I’ll see if fiddling with the heater helps consistently enough. I already installed an oil pan heater, but at 150 watts, I doubt it does much to help. At best, it makes the oil thin enough for the engine to start more easily.