Grinding type sound coming from passenger side of Mini Cooper engine.
Grinding type sound coming from passenger side of Mini Cooper engine.

TristanCooper

When i start my car on cold mornings i get a pulsing zinging/grinding type of noise coming from the engine area.

Hey Scotty,

Right off the bat, if you watch the video, the noise happens the first time about 2 seconds into the video, and the second time it happens is about 10 seconds in. i think it does it a third time towards the very end (20 seconds ish) but it's nowhere near as loud (I think it's gotten up to a high enough temp at that point to negate the noise).

On mornings that are 10-15 degrees F or lower (and the car is ice cold, if it has any warmth to it and it hasn't been sitting for hours, it wont do it (sitting overnight, then starting it in the morning is the best way to catch it making the noise)), I have a noise that's coming from the left side of the engine. The only things in the area that noise is coming from is the timing chain, water pump, and alternator. I should mention this is an 06 Mini Cooper (non-s). The power steering pump is electric so i only have those two things running by belt as well as of course, the belt tentioner. This noise as you can hear in the video pulses randomly for about the first minute. It doesn't happen as it's starting, and it doesn't generally start until about 10-15 seconds after it's running (enough time to start it, then run in front and listen to it). I'm having a real hard time trying to determine the cause, i wouldn't figure its the timing chain as i'd expect that to be more of a rattle, and i wouldn't expect it to pulse like this is. The alternator is working perfectly fine (i have a live data scanner and it shows that it's making plenty of power, on top of that i don't have any of the common signs that it's going out on me), the water pump also seems to be working fine, car doesn't overheat at all. I flush my coolant yearly with prestone premixed 50/50, the green stuff. The tensioner bearing seem to be fine, the tensioner isn't shaking while it's running, and when i pull it back and roll it by hand, the bearing doesn't feel pitted (although i know a bearing needs load on it to know for sure if its pitted). The only thing i could think of is maybe the antifreeze ratio is wrong, however like i said, i bought this premixed. Maybe the coolant is starting to slush up when it gets down that cold and I'm hearing the water pump pumping slush so that's why its making this kind of grinding noise? I'm really not sure, and i'd rather not just start throwing parts at her if i can avoid it. I have noticeable valve tap you can hear when you stand next to the engine while its running with the hood opened, but i wouldn't expect this to be related to the other noise i'm hearing as the noise is isolated to the passenger side only. There really isn't much on that passenger side, just the alternator, water pump, belt tensioner, the abs module is on the passenger side but its back behind the engine and i can easily get to it, i can tell its definitely not coming from the abs module. Other than those things there isn't anything on that side that is moving when the car is parked and running. I hope you can help because i am absolutely at a lost on this one. Thanks so much for your help, love your videos!

Comments (4)
No. 1-4
TristanCooper
TristanCooper

well let me rephrase that, i can't run the engine with the serpentine off for long enough for it to make the noise. Battery would die before it ran long enough to make the noise

TristanCooper
TristanCooper

Also, i'm not really understanding what you mean by remove the fan belts. The fans are electric, not belt driven. I've only got the one belt, which is the serpentine going from the crank, around the water pump, up to the alternator, back down around the tensioner and the back to the crank. I can't take off the serpentine and run the engine at the same time.

TristanCooper
TristanCooper

Hey Scotty, thanks for the response. I'm pretty well aware of the base model W10 engines being very weak unfortunately :(. I've got big plans underway for her though and this engine won't being staying for too long (I've already started building a much stronger W11 (the cooper S engine) for her using RMW forged internals, this one aint gonna be weak i can guarantee you that haha). If somethings gone inside, that just means my plans will have to get pushed forward so kind of a yay, kind of a shame. If it is internal, do you have an idea of what might be going on? and if so how long do you think she'll last? i take very good care of it, shift before 4k, oil changes every 3k, coolant every year, so it definetly doesnt get beat on. If it can make it till this summer, i think i'll be just fine. as i said earlier this only happens when it's really cold, so at the moment i might be okay because it is starting to warm up somewhat here. Here's to hoping though right! thank you :)

ScottyKilmer
ScottyKilmer

Editor

remove the fan belts, pray noise goes away then figure out which pulley is making the noise. If it stays noisy even with belt off, engine has internal damage. Realize those mini engines are VERY weak. My neighbor has blown two of them, she's english and nuts about those cars, keeps buying em