Hey guys, long time forum lurker and today I finally decided to join. So I bought a 2012 Cooper S with 113k miles a little over a month ago. I went with it because the dealer was reputable, the price was solid, and I heard the n18 engine had eliminated many problems that the n14 had. Soon after purchase I started to notice a ticking/rattle sound during idling. The best way to describe it would be a not too loud but prevalent tick/rattle sound. It sounds more prevalent on the passenger side of the car. You cannot always hear the noise, and performance is not affected. The noise just comes and goes. Naturally, my first assumption is the timing chain needs replacing. So I took it to Mall of Ga Mini dealer and they said there are no problems and I am probably just hearing the injectors. I’m afraid they just didn’t hear the tick/rattle at the time, because the noise only occasionally happens. Believe me guys, I have read just about all the threads regarding rattles/ticks and the things that cause them, but I still haven’t been able to pinpoint what the issue might be. The noise isn’t really present at all when driving. Sometimes it goes away as soon as I put the car in drive. Sometimes after my short drive to the bus stop parking lot it returns as I put in in park (usually the engine is nearly fully heated up at this point). Also, sometimes I do hear it during semi-warm starts. Does anyone know what the issue might be? I’ve read that the timing chain, turbo wastegate, Loose heat shield, vacuum pump, loud injectors could all be a cause of a noise like this. I will try to get you guys a video soon. But in the mean time I would love any input as to what could be the cause of this noise. Thanks for the help Miniacs. -Blake

 

My N18 sounds like its ticking too and I only have 61K on it.

 

Does it occasionally happen at idle?

 

Yup, sometimes louder than other times. Doesn't seem to matter cold start or not. Pretty sure its the valves that are making the noise. I saw my mechanic talking about one on the FB group a few months ago. Not sure why mine does it though, only been to the best mechanics and used the best oils. Bought mine nearly new too. I could see how yours might be different with more miles and unsure oil change history.

Perhaps some others will jump in here and give better explanations lol

 

Mine has developed some weird rattling only on cold starts, and remains there until the engine is up to temp. It sounds like something is loose.

 

The sound you describe is very consistent with the sound of the injectors at idle. Loud and Mini centric, but Normal and not to worry. Also, the turbo heat shield is notorious for rattling at idle. Similar sound to injectors. You can check for the shield rattle by opening bonnet at idle and pressing on shield - not with your hand, really hot. The shield rattle can sometimes be minimized by tightening the bolts that secure it.

we have both sounds with our 2013 S with N 18. 75,000 hard miles, including lots of track, and no issues.

 

I have a 2013 that just passed 44K miles. We bought it used with 34k miles and I too heard the ticking/rattle sound along with all of your descriptions in your OP. I took it to the Mini specialist (The Haus) here in Los Angeles for a thorough inspection after a few weeks of ownership and the shop gave it the all clear. I asked them about the ticking and they said it was normal. They even took off the oil fill cap while the engine was running and the noise got louder, but said it was definitely the valves and injectors. They said you would definitely notice when it's the timing chain. Hope that eases your mind. Enjoy.

 

Thanks for that info!! Also I want to take a look at Heat shield as mentioned above . . . just to check lol. Valves and Fan are louder than the exhaust

 

Update: so the ticking hasn’t gotten any better or worse, it’s still intermittent. Sometimes on cold and sometimes on semi cold starts. Car still performing as it should. I will check the heat shield to make sure it’s tight; but I am suspicious it could also be the belt tensioner as this is an higher mileage car. Me and my mechanic will take a look this weekend for further diagnosis. Will keep you posted.

 

Are you talking about the timing chain tension or the Serpentine belt tensioner?I would not want to be giving advice not to check into a potential timing chain tension issue, but please consider listening to another mini with an N18 engine to see if you don't hear the same kind of "rattling". The noise from the injection and valves is pronounced with that engine and is not, by itself, any indicator of trouble. You might save some money.

 

Our 2012 S does this as well, always has. As someone else mentioned, is most likely the fuel injectors..

 

My 2011 cooper s had a ticking/rattle at idle.
Red some posts about oil affecting this.
Did an RVS engine treatment and noise is gone.
I used it previously on my Kawasaki Z1000 for similar noise and decided to give it a try.

 

The thing that convinced me that the ticking sound my car makes is the fuel injectors was when I drove past a concrete wall at low speed, which reflected the sound and made it very audible. When I let off the gas, the ticking immediately stopped; stepped on the gas, it started again -- every time. This is a fuel-saving measure -- at least on manual transmission MINIs -- to deactivate the injectors when you take your foot off the pedal while the car is in gear and the clutch is engaged.

 

I see what you’re saying. It could definitely be the injectors. But I usually only hear this when the car is idling, intermittently. And in my case I have an automatic.

 

It would have helped if you posted a recording of the sound.

In the meantime, does this sound familiar? Try to listen to it through headphones or good speakers as there is a high pitch "squeaking" noise from the friction pulley's bearing, a "clicking" noise coming from the lose and rattling friction wheel assembly and a more pronounced, deeper knocking sound when the friction pulley engages the waterpump pulley.

For a long time I thought it was the timing chain and was very relieved when I found out it wasn't (the youtube video is of my actual car)

 

Thanks for the input. The sound I'm hearing is kind of similar, except I don’t here a knock or squeaking, just more of that clicking noise. I haven’t been that close to any of the pulleys or belts yet to hear if that’s where it coming from. I Will be taking it to my mechanic tomorrow, we will get it on the lift to get close up to the belts and pulleys and hopefully find where the noise is coming from (if we are actually able to hear it) lol

 

If the front right wheel and (at least the front half of the) inner wheel ark cover are removed, it will become immediately apparent. Listening to the noise from above the engine was no help and I did take the car to two different mechanics to listen to. Both were unable to identify the source of the noise.

 

By the way:
Apparently (some or all?) US versions of the Mini have the waterpump engaged permanently. In order to disengage both the waterpump pulley and the friction wheel assembly and listen to the rest of the engine, a release latch at the top of the friction wheel assembly can be pulled (see attached photo).