Anyone Know Anything About "low End Rumble" On Audi S4's - Specifically The...

I get a strange noise on start-up, usually noticeable when the engine is fairly warm, but sometimes from cold. Someone suggested it may be "low end rumble" but just wanted to get some more info.

Audi S4 Avant Overview

Debuting in 2001, the Audi S4 Avant was the first sports wagon (a cute modern term for a station wagon) to feature a combination of quattro all-wheel drive, 6-speed manual transmission, and a biturbo 2.7-liter, 250-hp V6. Part of the S4 line, which was itself a sports performance version of the A4, the S4 Avant offered the practicality of a people and cargo hauler, with the thrilling handling and performance of a sports car. The driver could seamlessly switch from responsible parent to wild child with little effort.

To complement its sports image, the S4 Avant featured a sports-tuned suspension without sacrificing a lot in the way of ride comfort. Inside, drivers could feel secure in the supportive sports seats with bolsters and special leather/Alcantara suede upholstery. All-wheel drive quattro action, 4-wheel ABS brakes, and an electronic stability program kept you rooted to the road, hugging curves, and able to enjoy the back roads in all weather conditions.

When it got a 4.2-liter, 340-hp V8 engine in 2004, the S4 Avant became a true sports car. Though it lost the turbo (and the accompanying turbo lag problem), it was able to do 0-60 in less than six seconds. Yet it still handled smoothly and maintained interior comfort. Not bad for a family station wagon. Not as roomy as comparable sports wagons, since it was still based on the A4 platform, rear legroom suffers in the S4 Avant, but when the seats fold down, there is 61 cubic feet of cargo space.

As with all Audis, the S4 Avant is luxuriously appointed, with power everything, xenon headlights, multi-zone climate control, heated seats and mirrors, wood trim, an MMI central control interface, cruise control, and trunk compartments. Special aluminum sports trim can replace the standard wood trim around the instruments for a little extra flash. In 2005, a new quattro system was introduced, with a 40/60 front/rear torque differential, to improve handling and stability, making the Audi S4 Avant a safe and secure family car, that is simply biding its time until its full power is unleashed.

Updated by Anonymous