I’ve had a clunking noise in my Audi A4 that only appeared in certain circumstances and was very difficult to narrow down. For about 2 years it’s bugged me and despite visits to various mechanics and having been put through a couple of MOTs in the meantime, no one has been able to identify the problem or what the solution might be. The problem turned out to be very different from what I expected and very cheap to fix.
A very illusive problem
The problem appeared a “clunk” when I rounded a corner. I’d experienced suspension problems in previous cars which had a similar feel to this so this is where I concentrated. There was nothing obvious that I could see so I took it to a local garage for expert opinion. After a good look around the mechanic couldn’t really pin point my problem but decided to replace a couple of parts which he suspected may be causing it. This probably wasn’t necessary yet and in fact didn’t solve the problem.
This was disappointing but I thought I’d keep an eye on the problem to see if it got worse and perhaps it would be picked up on the next MOT. When the time came, it passed first time! The problem hadn’t gotten worse but it was still there. I grew to accept it but it was niggling. Something had to done.
The problem was sporadic. Sometimes when cornering there was no sound at all and other times quite a loud clunk was clearly evident. So I needed to narrow down what under what circumstances it manifested itself. It only happened when corning relatively sharply, and only when corning to the right, but not every time. In fact 2 right turns in a row would only exhibit the clunk on the first turn, but not the second. This was very strange, what could it be?!
Identifying the issue
I went googling for ideas, searching for any suspension and steering problems, both general and specific to the Audi A4. There were a few avenues to explore but one unlikely cause caught my attention: a loose battery. Surely this wasn’t the cause? I remembered that it had been listed as an advisory item on the MOT but I never suspected that this was the cause, and yet I couldn’t rule it out. A quick look under the hood showed that the battery easily slid left and right, but not up and down or back and forward. It was bolted in but this didn’t prevent lateral movement.
This actually made sense, considering when the problem occurred. During a left turn the battery would slide right toward the centre of the battery but, but it didn’t slam into anything, it’s movement being stopped by the cables instead. During the next sharp right turn it would slide back to the left of car and slam into the side, creating the clunk. A subsequent right turn wouldn’t reproduce the problem as the battery was already fully left.
Finding a solution
The was the theory so would securing the battery solve the problem? The bolt securing the battery seemed inadequate and was directly under a brace making it very difficult to adjust. It was in place and seemed tight, but sitting at the very front of the battery was not best placed to prevent lateral movement. I decided to try making my own. I found a small right angle bracket and some bolts which would do the job.
With this make-shift bracket in place it was time for a test drive. I found a couple of roundabouts which I knew caused the problem, due to having to steer left and right twice in a row. For the first time in a couple of years I was able to corner the car with no unusual noises! It was such a small problem which caused so much frustration- gone. Sometimes the cause of a problem isn’t what you might suspect. The lesson for me is to pay attention to issues which are pointed out in the MOT. They may have consequences which you might not think of.
(by the way this articles featured image has nothing whatsoever to do with solving this issue…)