One of the biggest problems with Audi is that it builds some incredible vehicles that never make it to the U.S. The vehicles by the German automaker that do make it to the States can even go toe-to-toe with BMW. Audi is not impervious to problems, however. Car Complaints reports that there are a few problems with the Audi S4.

Engine rattle on startup

The Audi S4 didn’t have many problems reported at all. In fact, Car Complaints stated, “We don’t have a lot of complaints on file for the Audi S4 — feel free to add yours here. It’s either not very popular … or it’s very, very good.”

The No. 1 problem the Audi S4 has is for the 2005 model where owners hear a rattling sound when first cranking the engine. This is because Audi used plastic to build the plastic timing chain guides and tensioners. Since plastic isn’t exactly well known for its longevity—especially when it’s part of the timing chain—it’s rather shocking that only two people complained.

One owner was more surprised by the cost of fixing the issue than he was the actual problem. He stated, “Yes, even this website can’t believe it, but $7,000 is the real repair cost involved in an Audi S4 timing chain repair! The entire engine must be removed because the chain is between the firewall and the engine block. The chain itself isn’t the problem, it’s the guides that the chain uses.”

Other sites such as Repair Pal didn’t have a lot of information about owners reporting problems with their Audi S4 either. Even Reddit had very little information to offer. In spite of this, it’s a rather severe problem that leaves owners reeling when they get the repair bill.

The average repair cost is around $6,200, and it occurs around 129,000 miles. The timing chain tensioner must be replaced in order to fix the problem. 

Premature brake wear

Brakes are probably one of the most common problems a vehicle can have. Part of the problem can be due to drivers who don’t brake properly. On the other hand, a vehicle may have issues due to faulty parts.

In this case, only one person reported a complaint. The owner stated that she had to have the brakes repaired at about 16,000 miles. The dealer told her that she was too hard on the brakes, but she had to take it back to the dealer six months later because the brakes were worn down to 4mm and the rotors were warped. Her Audi S4 had 25,000 miles on it by this point.

There were only two complaints reported on the AudiWorld forum. One owner reports that they changed out the pads and rotors several times before finally trading in their S4. Car Complaints reports that it costs $850 to repair the brakes. 

The Audi S4 also experiences bucking

The third-worst problem reported for the Audi S4 was bucking. Some people may enjoy bronc riding, but the owners who reported this problem were less than thrilled when their S4 began bucking without warning. It was a scary experience for them that happened on multiple occasions.

It appears that the bucking started when drivers were forced to brake suddenly and then immediately tried to accelerate. One owner stated, “A quick brake, followed by quick acceleration leads to bucking and remaining revved up upon acceleration, and lunging forward while braking.”

It’s an unusual problem that was only reported by two owners. Neither was able to get help from their local dealership, even though one reported he heard the problem could be fixed by replacing the mechatronics unit. The bucking problem usually showed up around 5,050 miles. It’s not the only vehicle to experience bucking as some Ford Taurus models also had this problem, but it’s not a common problem for Audi vehicles.